Oh you absolutely get them for sexual reasons. And no WAY would I allow my girls to get one and if they came home with one I would remove it for them and then I would see to it the place it was done was shut down. I have a 21 y.o. DD as well, she was NOT allowed to have any piercings other than ears until she was 18. For her 18th bday she wanted a piercing, I paid for it, it was her tongue. Fine, she's 18, but not before. My 2 younger girls know that's the house rule and there's NO way around it. Ears are fine, anywhere in the ears, but no where else on the body gets pierced until after they turn 18.
To the PP who said they can't understand anything people are saying, you might be surprised. My DBF had his tongue pierced for 2 years before his parents noticed, and they only noticed because he stuck his tongue out at me and forgot they didn't know yet. LOL And yes, we see them regularly, sometimes too regularly! LOL He had his in for about 5 years, he just took it out not too long ago.
And to confirm, I'm not opposed to piercings, I've my cartiledge, my tragus, my ears twice and my belly button pierced. And I have a tattoo on my lower back and am designed another one.

Oh and I let my girls color their hair, they love bright colored streaks!