Maybe girls just feel unconfortable about men looking at them
i did not look my boobs when strangers looking at me, but I feel a little uncomfortable about it. i can not tell why. The feeling is so bad. Until one day, a friend told me that just indicated that you were not confident about yourself, so you had the bad reaction about it. And that is not really a big deal when male strangers looking at you. So, now i have no bad feeling about it.