Yeah, dudes will always look. They certainly did in Uganda. But I noticed--not nearly as much as they would have here in America. They were desensitized to it. Like breast feeding moms and ladies in the jungle were NOT the same as girls shaking it in a club. They were two different sets of boobs. It did not diminish their interest, but it put a realistic, less holy-grail approach to it all. And I found that refreshing.
And I'm sure there are some big-breasted women that prefer the support.. But honestly, most women don't truly need it for most activities that aren't plyometrics, work, and physical fitness related. That's a pretty personal choice and, for small breasted women, most of the bra focus is on covering just the nipples so they can't be seen.. the rest of the breast isn't really the concern.