I guess its all one in the same, but I always saw it as my standards getting lower vs them actually looking better. I mean, when you end up getting with a chick you already know and don't really see as attractive, I don't believe it is cause they are suddenly better looking...you just care less lol.
I typically use an average-looking waitperson to judge my level of intoxication. When they start looking pretty hot, I start drinking water! (mostly because at that point I've embarrassed myself and they stop serving me...)