I agree with Doc.
I work in a customer service related business and come across people from all walks of life. Though I may not agree with their lifestyle choice, if I made a comment upon it I could expect to not have a job Monday morning.
No matter where you go, you should expect some level of courtesy and professionalism from the people who work there.
I think you handled the situation well, though. You reminded him that people in glass houses shouldn't throw stones.