Here are mine:
-How many kits does team they have? is it a new one for each match? (since after all some of them are tossed to the audience and swapped)
-How do teams book for their flights (and hotels), I mean is it just a one way ticket and then when they lose they just get the next plane that has enough seats or do they assume that they will stay till the end and get a round trip flight for that?
-Has any team's locker room ever been sabotaged? was the perpetrator caught?
-What has been the worst injury ever on the field? (that you know of)
-Has the referee ever interfered with the play? (as in accidentally got in the way of the ball)