Citi Bank India Stopped Usage of Cards for Purchase of Crypto Currencies

Today I got a mail from Citi Bank saying that because of potential economic, financial, operational, legal, customer protection and security related risks asscoiated with Bitcoins and cryptocurrencies , Citi Bank has decided to not permit usage of credit and debit cards towards purchase of cryptos.

Now let me ask you a question how come using debit or credit cards for purchasing cryptos is a risk for economic. Financially people will become sound because it is one way of investment, I don't think it as a financial risk. They say legal risks, according to RBI there is no such notice to stop purchasing bitcoins or cryptocurrencies to it should not be legal. They talk about Customer Protection, are we really protected as you are the ones who give our details to credit card department and they call us numerous times in a day.

Your thoughts on this?