why would it be illegal to discriminate?

[r3vbr]

Isn't it in my right to discriminate against a group or race? not that i do, but why is it illegal for me to say ban blacks and asian people from my business (restaurant, store, etc)

As long as you dont cause physical harm to the other person I dont see why it should be illegal.
Also let's say I have a company and I make the following policy "no woman or fat people will every be promoted here". in a free society I don't see why companies are forbidden to do this

thoughts.