> The chances of someone mucking with my food because I tipped $1 on a $40 order are absolutely >0%.
More realistically, you'd just never get your food.
Drivers have the option to reject low-paying deliveries, and they absolutely will. I've heard of restaurants having a "wall of shame" of food that's been ordered and prepared, but is consistently getting rejected by drivers.
Eventually it'll land on a driver that is truly desperate or is just starting for DoorDash and wants to get some good reviews. Unfortunately, they'll deliver cold food that's been sitting on the Wall of Shame for half an hour and the customer will blame the driver for it.