Can they what. I went to the Warriors vs Manly Semi in 08 and a group of Warriors fans had got permission to bring their drums along. They'd gone through all the proper channels for it, but one wanker decided to have a whinge about it during the 1st half of the Toyota Cup game and security told them they couldn't use them for the rest of the game. Pricks. And of course we lost the U21 game in the dying seconds, then got thrashed in the semi... was a pretty crap day!
Yeah bro.
They used to be more lenient but in the past years. Well not to be prejudice but the Bulldogs supporters have been known to take drums and cause commotion and trouble with them (Excess noise and threat + creating a rowdy "violent" atmosphere) so they put an end to the drums unfortunate how one crowd ruins it for the res. Tried taking some in for Origin and got told no and had them confiscated. I got told this by the head security there who warned me about it and then gave my drums back after the game because I was nice about it.
Whistles because they can stuff the Ref's up in contact with the RefBox up in the stand (Don't ask me how this is what they told me). No idea how they would hear a whistle amongst the fans cheering. You can sneak one in though no problem lol. (I've had a few taken off me)
Vuvus because "They just can" and the noise they make annoys security (I just sneak in a pocket horn). I've had a few confiscated and lost most of my stash at Origin time.
ANZ have tightened up security big-time. Pretty sure banner's have to be registered down as well and go through the right channels for those to be in the game.