Hi Bob; Your question was good one.... if anyone gave it any serious thought, instead of the one-liner replies. I can tell you first hand that I have had waitresses I am friendly with in A.C. put their roulette tip chips away for me. I know of other waitresses in Atlantic City who bring home their roulette chip tips to their husbands who are collectors, and I've been offered the duplicates.
I've asked to purchase chips from waitresses on the casino floor, both in AC and Vegas. Sometimes they will sell them to you, sometimes not. This past visit to Vegas, my wife Brenda asked a waitress at Circus Circus if she would sell the roulette chips she had in her tip cup to her. The waitress replied "I don't know if they are .50 cent chips or $1 chips". Brenda said she would give her $1 each for them..... the waitress couldn't get them out of her cup fast enough. And yes, I sold the duplicates for $3@ at the show. Archie