Why don't some people learn to question things? Why stand on the status quo and be more of the same?

I constantly ask the same question. (I'm 15 by the way) people feel they need to "fit in," especially in high school, and I just don't understand why. What's so bad about being original? What's so bad about forming your own opinions from doing your OWN research? Many say "because it's easier." well then why do have an opinion, and why do you fight for it so adamantly? It's frustrating. Frustrating isn't even close to accurate though.