Yeah, it's a strange place to get a piercing. People can pierce just about anything nowadays. But, when people limit where it's acceptable for a piercing, there are ways around that 'rule'. I can show you pictures of people who have surface bars through their lips. Is that acceptable? Probably not, because it's not as normal as a regular ring. But it's still through the lip. So, where is the line drawn? A few years ago, I would've said the same thing as you; that piercings in places other than ears, nose, tongue, etc. were just weird and shouldn't be done. But, I saw the cleavage bar and my view changed completely, because I think it's a very attractive piercing. Anything else probably looks strange because it's not something you see. It's becoming more common to see lips or eyebrows pierced, but how often do you see someone with their arm pierced, or their cheek, the webbing on their hand? You don't. I've only seen one person in real life with a cleavage bar.
Anyways, I just want people's opinions on piercings in general, I guess. I maybe should have put that as the topic instead of just surface piercings. Oh well.