I frequented the "Arts" last night and after the bows had been taken, the lights went up, and people started to leave the call went up for a doctor as it seems one of the patrons has lost consciousness or at least was quite unwell. The theatre was still about 60% full at this point and while a couple of people, with one hopes some first responder* training, moved in. The vast majority of the audience simply stood where they were, in the aisles, in the corridors leading to the exits, basically wherever they could get a good look.
It might be news to people (and these were almost all adults I'd give an age or late 30s if not older) but standing about getting in the way while being unable to render any assistance yourself is
a) no help to anyone
b) going to may actively prevent trained people from coming to the assistance of the person in need of help.
So let's all remember if you can't help then either try and find someone who can help or do what you can to get out of the way of those who might be able to assist and are trying to get in. Crowding in to get a good look is of no comfort to someone who comes round from having a weakness or seizure in public to know that several hundred people stood about make sure they had all the details to tell when they got home.
*I think that's American terminology but it fits well enough.