I work at a restaurant that offers curbside service. That being said, a to go, is just like being waited on in the establishment. With a few differences of course, you don't sit down to eat, it's boxed up for you, and no server to try and track down or bug you during your meal. But the positives are the same, you don't have to cook or clean up!
Tips are hit or miss. Do I expect them? Nope. Are they gratefully appreciated? Yep! If I make tips hostessing, I put that towards kids lunch money, tooth fairy stash, or if I want to get a soda or something like that. But a lot of it is based on what your order total is, of course the service, and whether or not everything is in the bag and the order is accurate...