We cannot accept anything that has a cash value. In the past, on sUA, this included gift cards, but I think they now allow us to accept small gift cards for things like Starbucks. There is a cap (I'm too tired to find what it is, but it is relativly low.)
Years ago, I had a person so insistant that I take a $20 bill, that there was no polite way to turn it down (I had turned it down about 5x.) I finally accepted and immediatly went to mgmt and ask that it be used to offset the next pizza party we threw. That way, I didn't insuot the gifter, and I did not personaly gain from it any more than anyone else did, removing any question of it being a "bribe" or a way to influence my actions.