Of course they aren't the same, and all your statements are true, and "Uber for Food" also isn't the same, but the ultimate challenge will be the logistics problem (they admitted that their ultimate problem was logistics), and this problem is equivalent for all three. If you solve this problem for Food, you can beat Uber, beat anything else, just on this one algorithm, or you can offer your algorithm to Uber and other services.

Problem can be defined as pickup and delivery, on the fly, or offline (knowing all of the orders in advance). If you solve the on the fly, you've solved the offline problem. Picking up people, or food, delivering people, or food, problem in its essence ignores the subject and optimizes the pickup/delivery.