I live in the Netherlands and I honestly do not know ANYONE who does not wear a bra. And if you see someone who doesn't, people are bound to notice and think something of it. Unless their breasts are quite small, of course. I don't know what "Europe" in a previous post is referring to, as I wouldn't know what it'd be like in different countries, but in the Netherlands you're pretty much ought to wear a bra...
(Funny by the way, how Americans keep referring to "Europe" in that way. In Europe, this! In Europe, that! You can't really say that, cultures are VERY different from each other. What is normal in the Netherlands might be abnormal in Spain, and then I haven't started about the Easter European countries yet...)
I'm happy bra's exist. I have a B, so yeah nothing huge, but a bra does prevent my breasts from hoppin' along as I'm walking down some stairs... I had to wear them, I hated it at first though. But I started developing at 11 and was done around 13, so I guess I just used to tolerate them and later on, got used to them. On the upside, they do make your chest look better. Good for me, and a joy to watch on others...