I know. I used to work retail as well. Anytime I suspected anyone being drunk, underage, or anything that could potentially get myself or the store in trouble I immediately denied sale. A few times I had to have a manager come and back me up because the customer got a little rowdy. One of my favorites was a guy came in at like 1:30AM went to the beer aisle and bought a six pack, I saw him walk in, heard him talking to himself. A couple of things that tipped me off that he was probably drunk was: how he was walking, and while talking to himself he slurred a few words. I immediately denied sale when he got to the register. I called the night manager over and he backed me up on it, and we both agreed we could even smell alcohol from him.