Sigh. This reminds me of an ex-roommate.

So I worked at a factory and he was a notary or some such function connected with real estate, working from home. One day I was running late for work, which was maybe fifteen minutes away by bicycle, and asked if he didn't mind giving me a lift. About halfway there he mentioned casually, "Oh, just so you know, I'll be billing you at my normal rate ($60/hr) for this ride." Thanks for the trouble, just pull over and I'll walk, buddy.

People may or may not have sane ideas about friendship and money.

That's a weird comment on his part, but I think there is often a large mismatch between the cost that a carless person assigns to "bumming a ride" and the cost that the car owner assigns to that. If you are not a car owner, you may not realize how much of a pain in the ass it is to stop whatever you are doing and play taxi.

He believed that money was God's way of showing favor, and somehow that worked out to, "Anything I do to get money is okay." He ended up appropriating most of my possessions. This was of course the first and last time I asked for a lift from that guy, so if you like you can consider him to have appropriately valued his time and effort. However, not mentioning that until we were in the car and driving was frankly extortionate. As I recall, he did back down on the charge rather than pull over, but it provided an extremely sharp life lesson.

Yeah, the two choices are either provide a free ride or don't provide one at all. Billing people for rides is bizarre behavior.

The solution seems simple:

"I can't, I'm busy right now."

That's what people say when someone asks them to do something they don't want to, or where the cost outweighs the benefit.

Yeah, exactly. That's exactly how I feel.

If someone grabs a tab and sends me a Venmo bill, I'll happily send them their money. I would have rather grabbed the tab the next time. I won't be doing both.

(And vis a versa - If I say "I've got the tab" and the person sent me money, I'd be much less likely to invite them out in the future. I'd rather they just invited me out and grabbed a round.)