Yes, it is surprisingly difficult. Recently, I delved into FullCalendar many times, as I hacked into it additional features for my own purposes. It does not store information inside this form, but you can get it with a little hack:
Insert in line 4243 (in full calendar order 1.5.2)
t.eventResize = eventResize //add starts t.getShownEvents = function () { evs = []; for (id in eventElementsByID) evs = evs.concat(eventsByID[id]); return evs; } //add ends
Then do this to get an array of event objects currently displayed:
var evs = $('#calendar').fullCalendar('getView').getShownEvents();
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