I remember the first time I went to a theatre, when I was about 15. Theatre-going in those days was a special treat, something that you dressed up for. It was not at all unusual for the men to turn up in evening suits and bow ties, for example, and nobody would have dreamed of wearing jeans to a theatre.
The theatres were very strict about not letting anyone into the auditorium once the performance had started. If you arrived late, you couldn't go in until the interval and that was that.
In recent years, everyone looks so scruffy, like they've just finished digging the garden and then popped into the theatre!
I think the theatre is no longer viewed as "hallowed ground" like it used to be, unfortunately. Some people tend to treat it as an extension of their Iiving rooms and just do their own thing like they would at home, such as singing along or talking all the way through a performance
Standards have fallen, sadly.