The main downside of being pretty is, you don't know if people really like you or if they just like your body. Pretty people get depressed a lot, from what I have seen. I have a theory that it is mostly because pretty people can never be completely sure others like them for themselves.
Side note: Why do we assume it's always about girls? There are pretty guys who get pretty privilege...
It's important to talk about the downside of pretty privilege.
The extremely pretty people I've met often have a lot of trauma due to people being noticing them for the wrong reasons. I'm thinking of both a man and a woman I knew who were STUNNING, but even from childhood, people noticed for the nefarious purposes, and the adults used them for their own interests.
The guy I knew had been prostituted by his own father to fund a drug habit. The woman I knew had been molested by almost every man in power over her -- a pastor, a policeman, and a coach later attempted. Now of course, this can happen to anyone, but throughout their lives, these people knew they were magnets for such attention due to their looks.
I've also heard stories of people being nice to pretty people, buying them things, etc. and then demanding, or feeling entitled to that person's company (or more) because of it.
I recently read about a woman who grew up with pretty privilege that got her into the "IT" social scene. Because of her looks, her way was usually paid for (though at times, she was expected to make "payments" of her own.) As she got into her late 30's, she started to lose her looks, and now, in her 40's, she doesn't go anywhere because she's "ashamed to have anyone see me now." She talked about feeling suicidal because of this.
I think at one point, nearly everyone dreams of what it would be like to be extremely good-looking.
But when I hear about or read stories like this, sometimes being lost in the background isn't so bad.