I've run into this in restaurants more than anywhere else. I started to notice it when I was dating my husband--when we started going out, we took turns paying for meals, and the practice stuck. It got to a point where he was still finishing school, but I was working at a job that brought in serious bank. On "my turn," we might go somewhere more upscale. However, at some places, the waitstaff would completely ignore me while fawning all over him, assuming that he would be paying.
When I run into that, I don't go back.