What's On My Mind #5 / Prejudice

Why are people always being to prejudice anyways? I guess that's how the world works anyways besides money…
For example:
-all asians are smart (haha no.)
-white,black,yellow skinned ….. (still have no idea how that worked)
-girls always have pillow fights when they hang out together
-gingers have no souls (seriously where do people come up with that?)
-foreign parents are strict (sometimes not all the time)
-etc

Yup some prejudice world we live in….
Anime: SAO (Sword Art online)