In my experience I've gotten everything from a few comments to full on being showered with compliments. If you're into that and it makes you feel all special inside then great, but please don't expect anything more than that. In fact it worries me a little bit that they even say anything of that nature at all, considering how easy it would be for a guy to get the wrong idea.
My experiences have always been in line with the general consensus here, so I'm sure that I'm not getting special treatment. Professionalism as a client is by far the most important thing that you need to think about.