Your display ROAS looks great, so why isn’t it showing up in sales? It’s the question we hear most from cannabis operators running display, and it almost always comes from judging display by the wrong yardstick. Everyone wants last-click: the customer who saw the ad, clicked, and bought. But that’s not what display is or does. Display rarely earns the click. It earns attention — it builds recall and creates demand that converts later through a branded search, a walk-in, or a reorder. The return display generates is influenced revenue, and last-click can’t see it. Here’s how to measure what your display campaigns actually drive — a number you can defend in front of a CFO.

TL;DR: Display rarely earns the click, it earns influenced revenue that converts later through search, walk-ins, and reorders, so last-click makes it look worse than it is and naive view-through makes it look better. The number that actually answers “is this driving sales?” is incremental ROAS: the lift display causes over a comparable group that wasn’t exposed, measured against your POS data. Report blended and incremental side by side — the gap between them is the insight.

First, Two Ways to Count a Sale

Every ROAS number depends on an attribution model — the rule that decides which ad gets credit for a sale. Two dominate cannabis:

Last-click credits the final ad someone clicked before buying. It’s the default in most ad platforms because it’s easy to calculate — and it works for bottom-funnel channels like branded search, where the click and the purchase sit side by side.

View-through credits an ad that was seen but not clicked, when a purchase follows. This is the only way to capture display, CTV, and DOOH — channels people rarely click but that drive them to search, walk in, or reorder later.

Display lives in view-through. Judging it by last-click is like judging a highway billboard by how many drivers pulled over to call the number — you’d conclude the billboard did nothing, when it was quietly feeding every other channel. Demand last-click proof from display and you’ll cut the campaign that’s actually creating your demand.

Why This Matters

ROAS drives budget decisions. Measure display on the wrong model and you starve the channel that fills your funnel while overpaying for the one that just harvests it. In cannabis, where ad platforms are restrictive and much of the sale happens in-store, the gap between reported display ROAS and real display ROAS is often wider than operators realize.

What ROAS Actually Is

ROAS is revenue attributable to advertising divided by ad spend. A 5:1 ROAS means five dollars of revenue for every dollar spent. Simple, until you ask the hard question buried in the word “attributable” — which revenue does the ad actually deserve credit for? For display, that’s influenced revenue: purchases that followed exposure, not a click. The entire measurement challenge is figuring out how much of it the ad truly caused.

Why Standard ROAS Gets Display Wrong — in Both Directions

Last-click makes display look worthless

Display rarely gets the final click, so last-click hands the credit to whatever came last — usually branded search or retargeting — and zeroes out the display that created the demand in the first place. Your branded-search ROAS looks heroic; your display ROAS looks weak. Exactly backwards. The same blind spot hides the halo: display lifts walk-ins, organic traffic, and branded search it never directly targeted, and none of that shows up in display’s number. And in cannabis, where much of the sale happens in-store, last-click can’t see the offline conversion at all without POS integration.

Naive view-through makes display look heroic

Swing the other way — credit display with every purchase that follows an impression, and you overstate just as badly. A returning customer who was always going to reorder sees a banner on the way to the store; count that as ad-driven, and you’ve padded display’s ROAS with revenue that would have happened anyway. A raw view-through number isn’t proof either.

The fix is incrementality

The only honest answer is the lift display actually caused. Compare an exposed group to a matched control group and credit display only with the difference. That’s influenced revenue you can defend — see Incrementality for the methodology that separates ad-caused revenue from baseline.

“The ROAS Looks Great, But I’m Not Seeing It in Sales”

This is the most common thing operators say on a reporting call, and it’s the right question to ask. The gap is real, and it comes down to one distinction: attributed ROAS versus incremental ROAS.

Attributed ROAS is revenue that followed an ad exposure. Incremental ROAS is revenue that wouldn’t have happened without the ad. A display campaign can post a strong attributed number and still move your total sales very little because some of that attributed revenue is from current customers. The ad got credit for harvesting demand, not creating it.

And your total sales line is pushed around by things display doesn’t control: seasonality, pricing, the competitor that opened down the street, foot traffic, other channels pulling back. Display can be net positive and still get buried under those swings. 

The only number that settles it is incremental lift: compare customers exposed to display against a comparable group that wasn’t. The difference is the revenue display actually added, in dollars, not theory. If your reporting can’t show that today, run a holdout: pick a geo or audience you deliberately don’t serve, run it for 30 days, and compare. If the exposed group buys more, that’s your lift. If it doesn’t, change the strategy. Either way you stop arguing about a number nobody trusts.

How to Measure Display ROAS You Can Defend

• Connect ad data to POS data so revenue is real, not modeled from web events alone — and offline sales aren’t invisible.
• Measure incrementally: compare an exposed group to a control group and credit display only with the lift. This is the ROAS that survives scrutiny — see Incrementality.
• Multi-touch and view-through measurement, not last-click, so display gets credit for the journey it started.
• Separate new, returning, and win-back revenue so you can see whether display is acquiring customers or harvesting demand you already had.
• Pair it with purchase frequency — a returning customer buying more often is a different result than a one-time win-back, and the two shouldn’t be reported as one number.
• Pair ROAS with retention lift — a campaign that wins a first purchase but loses the customer isn’t profitable.
• Report blended and incremental ROAS side by side. The blended number is the headline; the incremental number is the truth.

What Good Looks Like

A defensible display ROAS report shows the blended figure, the incremental figure, and the gap between them — then explains the gap. When you can say “we’re at 7:1 blended, 5.3:1 on incremental lift, and the difference is returning customers,” you’ve turned a vanity metric into a decision tool. That’s the version a finance team trusts, and the version a good dashboard should give you without a spreadsheet.

Key Takeaways

• Display earns influenced revenue, not clicks — last-click can’t see it, so it makes display look worthless.
• View-through swings the other way and can overstate; the truth is the incremental lift display actually caused.
• Defensible display ROAS connects to POS data, credits only incremental lift, and separates new, returning, and win-back revenue with purchase frequency.
• Report blended and incremental ROAS together; the gap is the insight.

Go Deeper

For the measurement fundamentals, see our hub on marketing attribution for cannabis. For the methodology behind incremental ROAS specifically, Incrementality. For how display’s influence shows up without a click, View-Through Attribution and The Halo Effect in Marketing. 

DataJel reports blended and incremental ROAS side by side from your own POS data — and separates new, returning, and win-back revenue with purchase frequency, so the gap between “looks great” and “drove sales” is on the screen, not buried in an export.

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