Are you serious?
Yes, I'm beating this point to death, I know.
THE WHOLE POINT OF GETTING THE APP ON FACEBOOK IS SO I DON'T NEED OR WANT TO HAVE ANYTHING TO DO WITH GOING.COM!!!
If you can't figure out how to get me to use your service without having my e-mail address... or at least convincing me that giving you my data is useful by providing value first, don't expect to see me using your Facebook service anytime soon. Uninstalled. (Do not want!!)