Don’t forget in most cases the tips don’t actually go to the drivers. Doordash may guarantee the driver will make $7 for a delivery, then if you tip anything under $7 doordash will just pocket it. Seems like a good business model.
If I were to use DoorDash, this would actually give me an incentive to tip $0 via the app, since, otherwise, $6 of my fees+tips would be going to the company instead of the Dasher. I'd rather tip in cash (which I do have on hand at home, though I'd expect not everyone does, especially their target market).
Personally, I'd much rather have a delivery fee that translated to fair pay for the delivery personnel, instead of using tipping as an unreliable replacement for for/minimum wage. (At the risk of going off on a tangent, I'm OK with tipping for exceptional service/circumstances or for where there might be an extended/recurring service interaction, but I just don't expect that to be the case with "gig" delivery like this, unlike with traditional pizza delivery).
The UI I just looked at said something like "100% to the Dasher" under the tip selection.
Do you have evidence that they're lying about that (which might be outright fraud and thereby a risky move)?
Or are you saying something different, that if a customer tips $0, DoorDash has to pay $7 (or DoorDash pays $4 to make up for a $3 tip, etc), but if a customer tips $7 or more, DoorDash has to pay $0?
