No card swipes under R50

Why do you sell things that are under R50 if you do not accept card swipes for under that price. Your store in Montford shopping centre turned me away when i had a purchase below R50. That shopping centre only has one Standard bank ATM and i don't bank with them. What a stupid rule to have especially when people try not to carry cash. Won't be setting foot there again! Oh and please send the cashier and all future cashiers on train on how to speak to customers. Attitude and tone really needs to be addressed.