Im 15 pages too late and not going through this whole thread. This point is probably already made but racism is very harmful to the opressed race. In a racist society, there is a segment of society that doesnt just feel superior but has laws and societal norms in place to actually make them superior. If you are part of the minority now you have rules and laws that work against you which is does harm to a whole people.
Casual racism is harmless though. Is it wrong? Yea it probably is, but long as its not harming anyone and putting them in a disadvantageous situation, who cares? Theres many reasons people might not like me but none of those things hurt me. Someone might not like me because of my face, others my voice. Neither of those people put me in a bad situation. Casual racism is like that. Just another reason for someone to not like me, but its harmless.