The weapons are fully secure and their measures are far more stringent than film sets, etc. which is why, because of the protocols, this would be a tough ask. They are super careful.
On a side note, they wouldn't be able to do much when it comes to aerialists and any special effects, etc other than fire due to the ceiling/catwalk limitations of their existing equipment. On top of this, there are WAY too many pitfalls for people to mess around with under the stage when it comes to the elevator lifts, chemicals, high pressure systems, etc. that some casual third party performer could be injured by. They could train all of these people, but again, way more money and time than it's worth.