Bitcoin will be more risk for bank and could be again with bank, but until now bank given way for deposit money to buy bitcoin or invest on altcoin. Some day when many people using bitcoin bank will think one more time for allowed deposit money by bank. why not, everything is possible under the sun we see now. Looking at the trend that bitcoin is going it is likely to accepted in banks. It is a matter of time and change. Although it will not happen over night, since change is a gradual process.