No tipping here on pickup orders.
Absolutely on delivery or eating in.
Honestly, every place we order takeout from, a waiter/waitress doesn't deal with us -- at least that we can see. We call, we talk to the manager or owner (I'm thinking of my local Mexican place, mom-and-pop pizzeria, Beef O'Brady's and Dick's Wings), and when we pick it up, the manager/owner hands it to us and rings us up.
We just got takeout Wednesday night from Beef's. We know everyone there, and when we called, a waitress answered the phone. I said I'd like to place an order for takeout; she put me on hold and Wayne, the owner/manager, got on the phone to take my order. When I got there to pick it up, he took care of everything.
We're not fans of chain restaurants that offer the curbside thing, so we haven't experienced that. If someone ran out and brought me a bag to my car, I'd probably tip a couple dollars.