Honestly, I don't know, I've just always held banking info as something that must be treated as such. That said, it's not like I don't use credit cards on the Internet, but something about someone getting my bank account numbers does worry me. Plenty of people who know me well know my mother's maiden name, for example, and those two pieces of info together could spell trouble. I'm also in the camp of unless it needs to be shared, may as well treat it as private, and that includes encryption.