When I order delivery, I always tip generously because somebody actually got in their car or bike and came to my house with food. That's extra effort in my book. Same goes for when I eat in and have a waiter or waitress waiting on me, refilling my water, etc.
Certainly $170 is a large grilled cheese order, but more generally, I'm asking if it's expected to tip when you are not getting service beyond having your food handed to you.