Conforming to the "Norm"

In a world that's so diverse, how can society make so many people feel like there is only one "norm" in which they must conform?  I feel like some people conform simply because they want to be accepted, but who's to say the only socially acceptable norm is the one the media portrays? 

As a female I feel like my weight is not socially acceptable, like unless you look like a model you are just not pretty.  But I realize that what should be socially acceptable is being healthy, not overweight but not underweight. 

That's not the only thing I am talking about, some people think that everything is based on the way someone looks, way to judge a book by its cover... 

In this society we accept more, kids sitting in front of the tv playing video games instead of going outside to play, tattoos and piercings being frowned upon and discriminated against.

Our generation has given far to much control to the media.