Well, those people wouldn't be affected. Even those people with a profile could still create throwaway accounts for those other subreddits.

There are a few sub reddits where people are sharing real life information, so maybe confirmed profiles would be beneficial for them. I don't know if that just adds a bunch of cost and not much revenue.

I really think it would just ruin the simple, anonymous beauty of reddit to start involving identities. Leave that for IAmA :)

People go to reddit to get away from reality.