For banking, people just don't want other people to know what they do with their money, and how much money they have. Culturally I think it would be very hard to change. Not talking about dildos and such, but what you buy is really a window into your private life. When you start having children for instance, privacy becomes very important.

Thanks for the answers, it's an interesting perspective even if I strongly disagree. I wish people wouldn't downvote without giving their opinion.