Tee hee! Yes. Rude. What people don't realize is, there isn't a mandate from any higher authority actually giving them ownership of those seats. No flight attendant is going to come along and say, "oh, look, this nimrod actually purchased these particular 12 seats and we must leave them empty even if their guests don't show before the show starts." Even on planes, once the plane takes off, people can sit wherever.
In the future, I say, if someone is saving an ENTIRE ROW of seats, just take one. But be prepared to stand your ground if the other party shows. It may be a brawl to the death, but you have as much right to the seat as they do. And telling and elderly person it's saved? FOR SHAME! At that point, even if I was saving the seats, I would have given mine up.
You know, not all people honor the saved seat thing. I was behind a lady in a crowded movie theater once, and she was saving about 4 seats. It was getting hard to find seats and a couple came up and asked if the seats were saved. The lady said, yes, they are saved, and the man said, "Sorry, they're not here yet, we are." and they sat down! The lady was shocked and had to get up and find other seats, but you know what? Her guests weren't THERE YET! Other people were. She doesn't own the seats.
Making the argument, "yeah, but my party HAS to be late because they have real obligations blah" is just wrong, because EVERYONE has obligations. Just because you have one person in a group of twelve who can go an hour before the performance doesn't mean the seats can be held imo. MAYBE if there are enough to go around, and you want to be together, but not when there is standing room only and the performance starts. Nope. Wrong. You're depriving people who got there on time of good seats. THE NERVE!