Fosse76 -- Honestly, I have frequently been told something like, "Let it go for now & see what happens." The hope is that within a minute or 2, things will calm down. If you try to go & take control of the situation, sometimes the reaction is much worse than the original situation.
That's why people are sometimes seated before a late seating cue or assisted with an infra-red listening aid after the show starts but before a "good time" to hiode the noise of the transaction - if they create such a ruckus about not being seated or assisted, on the unusual but not rare occasion, they are helped at an incorrect time. Frankly, if I were in charge, I'd have them seated on the sidewalk, but that's another issue.
Similarly, when you have someone whose hearing aid is feeding back - this sounds awful to say, but it's true - it's often less disruptive to leave it & hope a person nearby will smack them in the back of the head (JUST KIDDING!!!) If you try to get the attention of a person with significant hearing loss in the middle of a row in the middle of a show to ask them to turn off their hearing aid, it can be extremely distubring to the people around them. So, FOH staff do their best to get the person's attention, but do often rely on the people seated around them for assistance.
To call it a policy, though, is to give it too much weight. It is often just a best-guess decision for that moment. We rely on common sense & assistance from house and stage managers - even actors spotting things from the stage. (The actors lying on the barricades at Les Miz used to be GREAT at catching cameras!)
The take-home is: please alert the house staff to disturbing situations, even of you think they know about it.