If physical money exist then bitcoin couldn't kill traditional banking system. And I believe it's not possible to exclude physical money from our life. I don't know what will happen after hundred years, but it's not possible in short period of time. Bank doesn't like bitcoin, but it doesn't mean they don't like blockchain technology. Perhaps once upon a time banks will start using blockchain ecosystem. Banks are worrying about decentralized system of bitcoin and they are more worried about volatility. That's why they are discourage to accept bitcoin as a payment methods.