To pay for lunch at a fast food place cheap or thoughtful?

Cheap and thoughtful. If you want to upgrade to impressive, you’ll have to upgrade your choice of restaurants.

fast food ain't exactly cheap these days anymore! Costs about $25 at Wendy's for a family of three. I'd say if the person I'm paying for can't afford it, then I'm helping that person.

It's equal to reaching (slowly) for your wallet with no intention of making the first move and then accepting the other person's offer to pay. It's just for show.

thoughtful

Any good hearted person will be grateful. If they've got expensive tastes, they might need to start paying for themselves.