Bitcoin and Ether are notoriously difficult to store securely and approaching the value of the global gold market. This is a $500 million a year business waiting to happen for one of Canada's big banks. Banks have the reputation, technical staff, security, and insurability, to become major players in the future market of storing cryptocurrency.
Cryptocurrencies liberate people from the need to use the financial system. There is no dependency on banks, except for exchanging to money, which largely relies on banks. But there's an opportunity for banks to go back to their roots as trusted places to store wealth. A Canadian bank could likely attract 5% of the world's cryptocurrency for storage if they could offer a secure, fast, insured service. It would immediately be used by institutional investors, high net worth individuals, and a significant portion of the individuals who hold smaller amounts of cryptocurrency.