Credit or debit cards, for starters, are nothing short of shoppers' Novocain. Even in the age of digital purchases and virtual money, we still attach a special value to dirty paper with pictures of presidents on it. Handing some of that to a cashier simply hurts more than handing over a little sliver of plastic.
When growing up, I saw segregation. I saw racial discrimination. I saw those signs that said white men, colored men. White women, colored women. White waiting. And I didn't like it.