Why does everyone have to use PR-Speak these days. "joins Facebook". That sounds like they're happy buddies going together now as equals.
Why not simply say "Moves was bought by Facebook". Nothing wrong with that?!
I think this is another example of a popular business practice a few commenters have been pointing out a lot recently: "ignoring the considerable power you wield over other people and expecting them to ignore it too." We saw it with that out of touch ceo [0], as well as both Theresa and Tom Preston-Werner.
In other words, they're using PR-speak because they've started believing it.