Grocery store food purchase functions don't work.

How am I supposed to buy food from the grocery stores brands like spar the gocer, food no*****s and no pick and no pay and and shopwrong checkers after university and after working at various employers if the banking and fincial services industries don't work correctly and or properly? Mostly just the card and merchant services and theres no self service so some prison guard cashier has to stare me down as a non shooper and or attempted shopper same applies to the malls.