I think it's relevant to ask in the context of "just what the hell do you think you're doing when you get up every morning to feed this thing? You do actually have to justify that."
If "this thing" is Google it's fairly understandable why someone would work there.
It's only been in the past year or two that Google's been popularly seen as focusing on G+ to the expense of users and innovation. Internally a lot of parts of the company are probably quite similar to the Google of 2010 which everyone liked.
And if they hate social networks what are they going to do, move to Facebook or Twitter?
