Everyone is always so easily "offended". It seems we have become a feminized society. Get over it. Did you ever try smiling FIRST? Maybe you'll get a more 'friendly' response....................
Having said that I would emphasize that I go out of my way (most of the time) to be courteous, even friendly, to service people when I am a customer. In restaurants, I almost always tip generously unless the service really sucks. I find that approaching people with a smile and a friendly attitude is usually reciprocated, and we both benefit.
That is not to say that I don't get really bad service sometimes. Especially annoying are service people who are otherwise occupied with a conversation with someone else, or allow themselves to be interrupted by a co-worker while they are supposed to be doing the transaction with me.
Just yesterday, I was in the men's clothing department of a store looking for some khaki pants, flat front, no pleats. The shelves were not arranged by size as I am accustomed to. I asked a clerk for help and as she was looking, a male co-worker came over and started talking to her about a candy bar he was eating. She stopped looking and started talking to him. It was like I was invisible. Then he left and she resumed looking for my size. As I was explaining to her what I wanted, some other customer came over and interrupted, looking for something else. She just left to go show him where some 'bama shirts' (whatever that is) were! I left the store and went accross the street where I found exactly what I was looking for. Spent my money there.
I have come to expect less and less "service" from the "service sector", but would not hesitate to discontinue doing business where my business was not wanted.