What’s more likely? That they were banned due to misunderstandings of what these devices are, or that they were banned they are “causing a disturbance”? Can you find an example of such a case? I’m not sure why this feels so important to defend.
There are several definitions of security, but the most relevant (in this context) are:
1. the state of being protected against or safe from danger or threat.
2. the safety of a state or organization against criminal activity such as terrorism, theft, or espionage.
3. procedures followed or measures taken to ensure the safety of a state or organization.
I fail to see how these devices fall into those definitions. I also don’t see how beach balls do either.
So if your argument is changing to: it isn’t security, but rather preventing people from getting in each other’s way (large signs, strollers, beach balls) I once again don’t see how that applies.
I agree those items have nothing to do with security either.
I'm not changing anything -- my root comment in this thread specifically mentioned "disturbances". Mitigating disturbances to the proceedings of an event is plainly a part of event security. The "threats" evaluated in event security are not solely to life and limb but also to the proceedings of the event itself. I didn't think this required elaboration; I thought most people would be familiar with this function of event security.