Interesting analogy. As somewhat of a Star Trek fan, I find the concept of a Star Trek convention more compelling than a JW convention. Would I ever go to either? Probably not. I can't sit through even one minute of a legitimate JW talk online, let alone sitting through hours of it.
As for standing around listening to an actor reminiscing about "that time I was playing 'Let's pretend'", I couldn't be arsed!
I went to an Amway EXPO once; does that count?