should be General Rule. Latecomers be seated during intermission. They would wait in thr lobby or foyer watching from a video screen what is on stage.
On Broadway?!?! HAHAHAHAHAHA!!! It'll never happen. Opera audiences (and companies) have entirely different views and expectations. And if that is the policy of the Lyric in Chicago, it is not embraced among all other opera companies in the country (or the world, for that matter). Not being seated until intermission is EXTREMELY rare and often depends on the configuration of the theatre and/or the staging of the production as well as the availability of seats.
Speaking of Chicago, the theatres running the Broadway productions often CAUSE late seating because they refuse to operate dedicated windows for Will Call pickup. Meaning, even if you show up early enough, you can end up waiting behind people choosing to exchange their season tickets for other performances or people simply buying tickets to future performances who want to chat about all the available dates and seating options and call their friends to discuss them, etc. and the box office staff lets them eat up all the time in the world with people begging to pick up their tickets for THAT PERFORMANCE. It happened to me and a group of about a dozen people had to wait until after the opening number of Billy Elliot to be seated, at NO FAULT OF THEIR OWN. The house manager refused to come out to speak to anyone. The production company ignored letters to them regarding the incident. So, when these complaints come along bitching about how people have get their panties in a twist because they were distracted for a few seconds, I just don't care.
Sh*t happens and if it happens to you, just hope you don't get treated like garbage for it, especially when it is out of your control.
"What can you expect from a bunch of seitan worshippers?" - Reginald Tresilian