I don't know if you live I the US, but if you just start walking around with five dollar bills and start handing them out, you really don't know what kind of reaction you're going to get. I tried giving my AT&T guy $20 for waiting for me, he wouldn't take it. Perhaps I could have insisted.

Americans can be deeply sensitive to people thinking they're poor and in need of assistance. And five bucks is practically nothing. Most people might well just take it to Starbucks anyway.