Assuming that you weren't in New Orleans during Mardi Gras, I'd assume that you don't flash everyone. So, I still think that it sounds like an "unscratched itch", lol. What can I say, I like euphemisms.
I think that through the last couple of decades men have come to understand, whether by the media or accusations of sexual assault, that you should never assume anything. Given the background of drinking, there was even more reason to give pause and consider the flashing simply the actions of a tipsy woman, and not a "come on". I mean, how many times have we seen the behavior of college aged women during Spring Break celebrations who flash and strip naked on occasion, outside of the club settings.
If you are thinking all that ^ when looking at a woman's tits then there is a problem with over analysis.
She is upper thirties in age and not on spring break.