Some Fox executives say they didn't like that fact that an admission was to be charged to the four hour event (Hannity just part of it). The admission was only $5 to $20, probably to cover expenses and a little profit for the organizers.
Maybe nothing was charged at the Beck event, but I wouldn't be surprised if we see other changes and restrictions at Fox in the future. Lots of odd occurrences around Fox in the past few months.
I think you are close. To my knowledge, there can be no charge for an audience for a TV show. Some Fed stuff. It is possible that FOX found out about the charge too late to check to see if the minimal charge for a different party would be OK or not. FOX understandidly (sp?) pulled Hannity rather than risk millions dollars of fines.
Why does everybody get so upset with FOX, Hannity or whoever before the facts are known? It happens so often!