It sounds like, in one case:
1) Doordash takes order on their site
2) Courier shows up to pick it up
3) Order never got to the restaurant, customer is confused, customer blames restaurant.
In the phone example:
1) Doordash connects the customer to the restaurant
2) Customer tries to place an order based on outdated info
3) Restaurant is now trying to convince the customer that the menu they are looking at is wrong. And restaurant looks like a fool because they can't even publish a menu.
In both of these cases, Doordash is damaging the restaurant (at least their reputation and wasting their time) and doesn't sound like they're making any good-faith effort to be a good actor here.
Also, in your example, if it gets to food being made and then an argument about price, what happens to the restaurant if someone refuses to pay? They don't really get to put that cooked meal into a fridge and wait for someone else to order it. It's garbage (straight up lost money) now.