a couple of years ago I tried to pay a $60 co-pay at a doctor's office in cash as they said I had to have the co-pay at the visit and they refused to take it wanted a credit card I told them I don't have one and I left my check book at home and had cash, if they couldn't take it they would just have to bill me. It kind of made me mad, so I waited for them to bill me twice before sending it to them.