That's the whole point. Customers who are price-sensitive do use the app to order, while people with money to spare don't bother.

That's why McDonald's does it. It's the same thing grocery stores have always done with coupons in the weekly flyer -- customers who are price-sensitive cut them out and use them, while people with money to spare don't bother. Or with clothing sales -- people who want the trendiest clothes at the start of the season buy them full-price, while people who wait until the end of the season get them at a steep discount.