Losing touch with coolness

OK, that in itself is no shocker. I am a thirty something stay at home mother of two. Its hard to keep up. I was at McDonalds today (there is nowhere else in Petersburg) and I saw something that got my crazy brain going.
There were some kids hanging out. (That's not the crazy part. I understand hanging out.) There were two girls and a boy. They looked very young. I'm not good at guessing ages but I really don't think they were old enough to drive. How did they get there? They didn't seem to be with anyone else. There were no bikes or scooters or alternate forms of transportation that I could find. I guess they walked from somewhere. Good for them. (That's not the mind bender either)
The 2 girls looked to be 13ish. They were both skinny little things. Their clothes made them look even smaller. They had on tight t-shirts, short jean skirts and leggings. (They really kinda looked like they had raided Madonna's closet back in the eighties.)
But something didn't seem right (besides the clothes) Each girl had a huge can of Red Bull. These cans were bigger around than their arms. I finally decided that was part of why the scene seemed odd. Secondly, they were using these drinks as a prop while they charmed this young fella. If you were spying on a dinner party of rich people talkin' it up, the girls were holding their drinks just like the richies would hold their cocktails. From time to time they'd take an oh so tiny sip. No offense to the Red Bull people but doesn't that stuff taste like cough medicine?! And what do a couple of little girls need a supersized energy drink for? Red Bull gives you wings but these girls were tiny enough to take flight if they walked into a breeze.
I guess I'm just not sure. Was this strange sight what all the kids are doin' these days? I sense that I've gotta lot to learn before my kids get older