I sort of think that if you're naked with potential sex partner, or during or after, that's not unusual. Most girls I've been with had no problem looking.
As far as clothed walking around in public, when I was younger I got a lot of stairs wearing Levi's 501's. I went to school in a city where walking was the way most people got around, and the crotch looks ranged between quick glances to blatant stares. Some even glared and smiled, then looked me in the eye, then looked back. Got a few "Hmmm" as they passed. Walking can be a great source of stares.