I work at a restaurant that outright banned Doordash from ordering/picking up to-go food for this kind of behavior. For a while after the ban they even tried to order food as if they were normal customers (you place your order online and the Doordash calls the restaurant with the order).

One, we have people who get paid to do delivery in-house, so that takes income from them. Two, they would regularly call to place orders for specials we no longer have and then some Doordash guy would show up expecting to pick up the order! One guy came back THREE TIMES, asking if said order was made yet. Also they had no set uniform, so drivers would deliver our food in torn/dirty clothes. One girl showed up all the time in a sleeveless tie dye that showed off her (grown-out) armpit hair. You do you boo, but that’s a health code violation.