However, Google wants to control the means by which you control your information.
In social media, you would normally use a range of online identities across several accounts to control your information. At least, the net-savvy do this. How many of us have an email account to use when registering for services .. to catch the spam? We control information flow, in part, by our pseudonyms. Of course, criminals hide behind pseudonyms and people with an axe to grind can create a fake facebook (say) account in your name as a way to smear your name. Also, using a pseudonym yourself can make it difficult for people who know you in one social group to find you in another... that's your trade-off.
In this environment, Google+, by policy, does not allow pseudonyms (handles, avatar names, nicks, whatever) as the main identity of the account. As you can imagine, this is the cause of some concern. There is even a petition.
There are lots of legitimate reasons someone may want to use a fake name for their account. The various articles and blog posts on this topic list them. The whole concept of pseudonymity is complex, here's an academic overview of the issues and concerns (as opposed to a bunch of bloggers with their backs up).
Using an obviously fake name is all that is being banned, in practice. If you really really need a fake name, make one up that sounds plausible. An obvious fake name advertises it's fakeness and so is more honest, so this policy discourages honesty. Note, user +John Smith will probably want to be more easily separated from all the other John Smith's out there: so a fake name can help people find you.
Without repeating the details from other blogs (above), it looks to me that the concerns of the users and those of Google can be addressed quite simply:
- Allow pseudonyms in the profile name.
- Encourage users to add their real name (however defined) under also known as.
This way, users can control which of their circles can see that part of their identity: adding to their control rather than removing from it.
Why not do this? Well I can only think of one reason: Google wants to know who you are. This is not about crime, spam, or finding people; this is about control.