Some religions are based upon the worship and veneration of departed ancestors .
My daughter was a competitive figure skater . Many of the other young girls were of Asian heritage . There Mothers were highly educated either MDs or PHDs . They would scold their 10 year old daughters for not working hard enough telling them in anger " you insult your ancestors by not working " . " Get back out there or no food for you " !
My favorite was " you hurt ancestor -- you sleep on floor ! " .
So Bigotry is an individual belief system . It works for many people and gets them through life day to day .