As long as it's opt-in I don't find it that creepy to be honest.
Honest question, I don't use Facebook so I can't tell from experience.
(I see what you're trying to say, that people are forced to install two apps instead of installing one - I just disagree that having two separate apps is "forced" while having apps bundled together is "choice")
"Hobson's Choice"
http://i.imgur.com/qsRdwaU.png
Google...