I'm one of those people that has never learned to drive and i know nothing about cars... I'm guessing from the comments that the joke here is that the stuff attached to the steering wheel will explode in the driver's face if the airbag is activated, is this right?
Rhinestones aren't really that sharp though (unless they're the really nice glass ones which I'm assuming these are not). It's also likely that at least the first two are plastic backed sheets. I can't imagine they'd be worse than the sharp metal logo usually on there.
Disclaimer: I know more about rhinestones than cars, which isn't a lot