Flying with a college buddy of mine, I was in the forward part of Y, he was closer to the back. I paid for a Jack and Coke for me and figured he would want one too. So I told the FA to give one to the really tall guy, mustache, and camo hat towards the back of the plane.
She laughed a bit and said no problem. A few minutes later I hear a "yea buddy" from the back. Just pony up the $7.