Google+ doesn't export email addresses that you don't already have access to--for example, if someone has you in a circle but you've never exchanged an email. That makes sense, because the export shouldn't violate the privacy restrictions enforced by the normal UI.

However, in you can't export an email address already connected to a profile (either through contacts import or because the user shares it via privacy settings). So, the point is that Facebook is impeding export in a way that does nothing to improve a user's privacy but does create obstacles to moving your information elsewhere.

What you are claiming simply doesn't seem correct to me. I am too privacy conscious to simply use a tool so early in its release, but my understanding is that most data can be extracted from Google using google.com/takeout. I know I can export my Google Contacts quite easily, and I have done that before in order to sync with my home phone (i.e. ipod touch).