The real names policy on Google+ was long removed. You can use any pseudonym and don't have to share your real identity. In this respect, it's definitely better than Facebook.
It's not necessary to provide your phone number if you don't want to. It does not force you to do that, although for account recovery purposes (getting access back to an account if it's compromised), it will bother you once in a while to add your phone number as a recovery mechanism. I see this request coming with plain Gmail and Yahoo Mail too quite often, and just choose to skip it whenever asked.
If you use the Android platform, I suspect that Android device UUIDs may be transferred via Chrome or App usage.
This has some benefits -- Google have quite good login-pattern tracking, and alert for logins on new devices (or devices not used for a time). OTOH, it is also, quite obviously, a mechanism for tracking patterns of use across IPs, locations, devices, etc.
