Why are some people so concerned about race . I have seen some very ignorant questions on this sight?

Basically some of the questions range from why are black people so rude and loud to comments like all blacks are welfare reciepients just because they wear certain clothes. I think what happens is the thoughts of conscience and unconscience racism and beliefs about certain races are ped down generations and taught through generations. its amazing how many people today in 2008 have so many racists thoughts and it saddens me. why cant people just live there lives work, spend time with there family and friends, old and new whatever there race and just be happy and content?. also i think the thoughts that have been ped down were purposely placed so that there would be an invisible mental block from any race to keep them thinking at the level they are meaning black white asian hispanic or any race the person may be done to keep a level of separation or it could be the level in society such as cl that affects the way people think. whatever the case may be cant we all get along ?