Eyelashes permed?
I think a few treats are okay, and self-expression is fine, up to a point. I'm okay with haircuts and hair dye, since they aren't permanent. Same with eyebrow tweezing and occasional waxing, and more regular waxing for things like mustaches.
Entitlement is a problem, absolutely - but that can come from other things too, like expecting the latest iPhone, designer clothes, or a car. It comes from expecting parents to drive them everywhere or missing the bus because "Mom can always drive me and the bus is gross with 8th graders on it" or whatever the complaint du jour is.
However, I think parents going broke is wrong, and I think kids expecting parents to pay for it is wrong. I also think that an excessive amount of "correction and improvement" can be bad if it means the teen girl is unhappy with her looks or feels she isn't okay or acceptable the way she is. If she's doing it to please a guy, or if she's beating up on herself for not being "as good as" the others, then that's a huge problem.