I get that, and in general I'm an over tipper especially at restaurants, and a sucker for almost every tip jar anywhere, even on small purchases. What's surprising is how expected it is, to the point of being completely unappreciated. Tipping a dollar for a <$2 coffee is pretty generous; at least act like you appreciate it with a slight head nod or smile. I almost want to reach back in and take it so I can give it again because maybe they didn't notice like Costanza did at the pizza place.

As for van drivers, I think the dollar per person is usually not enough so I'm usually in the 2-5 range, although I guess it depends on what they make overall, if they are driving on a set schedule, their attitude, etc. What grinds my gears more than anything they do is standing there hands folded while you wheel your bags to them and they just look at you like they have no idea how they come apart or how the handle comes down when you know they know how it works. Unless its literally their first aircrew pick up ever, standard crew bag hooks and handle releases shouldn't surprise anyone.

That and the pile of randomly laid out bags with crews literally reaching over each other desperately trying to get their dollar(s) into their hands. Expecting a tip so much that they make you go out of your way to give it is kind of annoying.