Please. Stop. Asking.
Every time you ask me how I am doing, for some reason, I think you actually give a shit and I tell you how I am then politely ask in return, "and How are you?" Because I am a genuine person. I care. I may not care too much, but I am at least going to return the sentiment. So when you don't answer and bustle on with my order, I feel like a chump. I know it's part of your job or whatever, but please at least acknowledge I was talking to you or just don't fucking ask me at all.