oh ive been there.
i had the manager at a mcdonalds refuse me once, so i ended up showing him the law on my phone... which didn't convice them... so i emailed corporate, who called me back, and the store... and then the store had the law printed on the window at the entrance...
the next time i tried it there, had to still get a manager who said "i'll just do it this one time"
and i kept letting him know that i know he has to every time...