- Google wants more users in Google+
- People don't care about Google+
- This doesn't change the fact that Google is still afraid of Facebook and wants more people to use G+
- Google will try to do everything it can to drag you into this service which you won't use anyway
What's so strange about this?
-100% false for people using Google+ (absolute percentage unknown)
As you said, why is it so strange? It makes a lot of sense from a marketing point of view (the business strategy dictates so) and an engineering point of view (they already have a commenting system for users).