That works good in a world lavish with altruism....but, where I live (in a cosmopolitan area) it's a free-for-all. You basically take the money and run. No one is going to say what a nice fellow he was (me) not asking for reimbursement, let's "make sure we hire him in the future. You're forgotten within 8 minutes of your last conversation. I've heard of instances where it went as far as 12 minutes though!
Mark
........I recall the days when our band was just starting out (high school) and a 'client' would say "Play this one for $x - much less than the going rate - and the next time you can name your price." ... STILL waiting for the "NEXT TIME" ...