Another is evidence of crime and sabotage of the system. They wage open warfare against those who have for so long waged secret warfare against them. There are other consequences, too. Racism is very expensive. All of this costs money.
Racism makes a whole country simply look bad.
One may point to the universal condemnation of South Africa for so many years, and how it was excluded from participation in world events and world trade. Racism as directed at Roma in Europe has many origins. Color prejudice is just one of them. But color was not the reason for the initial enslavement of Roma in the 14th century. Unlike the enslavement of Africans, Romani slavery grew out of the desire for a large and unpaid labor force.