Not possible life without bank because many people need to borrow money from the bank and make their business, not available for borrowing in bitcoin and altcoin and then not have institution available for every one could borrow bitcoin or altcoin, now day many country have several bank kinds and give good service for every one to save their money.
But it's not actually the banks who own money they give out, it's mostly deposits of other people. They are just acting as an intermediator between two parties. Instead of borrowing money from a bank we could just have individuals borrowing and lending money to each directly. With the technology we have today this would be easily possible. And this would also lower transaction cost for everyone involved. Except of course for the banks as they make so much money with the interest rates.