As someone who has a personal G+ account and doesn't mind, and who runs a company that pays Google for apps for my domain on which we manage our email, I still had to register for G+ to be able to use the hangouts product in invitations and threads I'm having with my work email. Now that I've done so (without adding a profile photo or anything else), i'm getting tons of people adding me to circles, etc., which I don't want. It's essentially forcing a social-connection construct on a relationship with an empty profile that I don't want to create or have to maintain.