Why do people from all races care so much about what society thinks?

i've noticed that every race…especially with the women…all have some securities about something…whether its their hair, skin tone, body shape, height, whatever! why are people of every race think that they have to look and/or act a certain way to get people to like them? why not just look themselves and act like themselves, im not saying all people are like this because i know there are people actually proud of who they are, but for many people why, just be truthful about it… and im not going to single out a certain race either cuz we all have our issues and u know it, this goes for biracials as well