I don't know if buying Bitcoin on a credit card is a good idea, after all most people do not earn the amount of money that allows them to have a small interest charge on their card if it's not paid off so we are looking at people buying Bitcoin and then paying the money back at something like 29.6% per month interest ( using interest rate for one of the cards for high risk or bad credit ) which in turn will make their purchase very expensive. So they buy them - then what ? Sell them straight away for a quick profit or hold on to them in case the price goes up and they can make more ? Most people are not knowledgable enough to know what to do with them once they have them ( myself included )
what if it's a bad month for cryptocurrancies ? Do they then try to buy more hoping to recover their money if the market takes off again or do they sell and try to recoup something yet end up with debit for the balance ?
It really could end up a big financial mess for so many people