Wanted: Flattering Fitness Wear

Last weekend, I was invited by a friend to join her as a guest in a rather exclusive fitness club. Don't ask me what the annual membership fees are; pretty hefty, I would guess, judging from the facilities.
While I did enjoy the experience, I got the feeling I should have turned up with a more flattering gym wear. Does anyone else get the feeling one has to sort of "dress up" when you go to the gym? It probably doesn't matter if you just run 'round the neighborhood in your sweat pants, but there's something about going to a gym, a swanky one at that, that makes you more conscious of how you look.
So I've decided to get myself a new tank top with a discount code I chanced upon on DailyDeals.com. I'm not quite ready for those camisole tops that bare the midriff, not until I lose a few inches off my jelly belly, but my arms and shoulders are fairly toned, so a racer back style should suit me well.
I know many people would think it's a bit juvenile to dress up just to work out a sweat, but I say, if it inspires you to be more consistent with your fitness program, why not?
What do you think?