Credit cards can absolutely be used to buy weed. There are noy supposed to be ATM machines in potshops either, but some of them have an ATM anyway.
Learn something every day! How does the pot shop clear the credit card charge slips through a bank if the bank is not allowed to facilitate the sale of drugs?
Or are the shops not disclosing what the charges are?
Buying Randall Made Knives and Randall 1911 Pistols