Be realistic dude
Its 20 bucks you gave away, you have a car, so im assuming you already know how hard and fast you can get fucked for money by legitimate sources, license, insurance, plates, gas, tranny...fuck the people associated with owning your car have already robbed you blind, and you havnt fucked with any of them.
You knew better going there, you robbed yourself
But if you really HAVE to do something, understand him first.
Hes 27, lives with his parents, has no life and sadly, by 27 no way of ever having a decent life. If you understand the sad sorry state of his existance, then throwing a 20 dollar bill at him and up his nose is laughing at him. any Floyd fans out there? think Dogs, from the album Animals. laugh all the way to a better life.