IK, yes, after I wrote my post, I thought that "ligaments" must not have been the right word. I did a quick Google search, and here is a short synopsis of the study I mentioned, by HuffPo: http://www.huffingtonpost.com/.....62114.html. HuffPo says that it's the muscle that develops in order to support the breast. So maybe it is ligaments, but it's in the muscle and not the breast. I will say that I enjoyed Rae's comment about the National Geo ladies. :^)
I guess that since I am quite small, I view a bra as an accessory. Will wearing a bra make a difference in outfit X? So it's optional for me, depending on what I want my clothes to look like from the outside. Or if I want some lace in my outfit, I can just wear a bralette, even though no one will see it. So it's more for me as opposed to for the public.
One of the reasons I started going without a bra occasionally has to do with body image. One of the earlier commenters talked about body shaming. I had a lot of body shaming as a child. I think that quite honestly, many small-busted women who choose to wear a bra but don't really need one feel ashamed (due to the culture) of their body, because we aren't supposed to be able to see a woman's nipples, etc. Well...women have nipples, and that's normal. :^) It's not our bodies that are bad; it's that the culture says it's bad. I notice that if a woman wears a very low-cut, tight top with a push-up bra in order to show cleavage, that's considered OK because it's "sexy." But if that same woman goes without a bra in a slightly clingy top (not body-con, just slightly clingy) such that you can see the shape of her breasts and, heaven forbid, her nipples, that is considered disgusting—even if everything is covered up and no cleavage is exposed. How is it that the normal state of the woman is disgusting, while the push-up-bra-plus-cleavage is considered OK? It's like it's not OK for us to have regular bodies, but a sexualized body is OK.
I'm not trying to get on a soapbox or anything! These are just things that I've noticed while I've been thinking about body image. Sorry if I've offended anyone! :^)