Is there any place/social occasion where it is actually acceptable for a girl to go bra-less in the US? How often have you done this or seen somebody doing it and how did people around you react to it?
The following are the place/social occasion why girls (not only in US but anywhere in the world go bra-less: 1. Home (place) 2. House party (social occasion) 3. Cocktail parties (some dresses dont need bras) 4. Special dates 5. Family Reunions 6. Beach (especially when girls dresses not so see-through) 7. Clubs (yea, you can't easily spot on it but most girls do bra-less)
If the outer garments don't really need a bra to keep things in place, then going braless perfectly acceptable. A sun dress is the easiest example of such a garment. Obviously, the smaller the breasts, the more opportunity for "acceptable" bralessness, as more garments will provide suitable "restraint" or cover. The built-in shelf bra in camisole tops is an example of a garment that will permit smaller-busted women to go topless and it be acceptable by general social standards. For virtually all breast sizes, a white top requires the underpinnings of a bra.
I tend to go bra less at midnight when im going for a late night snack but of course I put a big jacket over so and keep my arms folded so no one will really notice as far as broad day light with just a t shirt on and big or small breast out freely thats a no no its just to me inappropriate trashy and is jusy a way of asking for the attention of any cute guy that you may pass by