This story is from 2013, and it's a well-written and fascinating look at the group and why it fit into the '70s and '80s games, but would be laughed off the field now.
Part of their appeal had to do with their sheer numbers. I never even thought of that.
"Back then, there were no giant screens that allowed people sitting in the upper deck to see the face of a superstar performer. Back then, nobody thought to recruit a mega act to do a halftime show. At that time, said Steeg, the theory of the halftime show was that it needed to “fill the field” so every person in the crowd would be close to the performance. A lone performer on a stage at midfield would have been lost to ticket-buyers.
“You couldn’t have a centrally focused, one-person type performance,” Steeg said, noting the lack of giant video boards. “What you were seeing was what you saw right in front of you. You didn’t have the ability to look to your right or your left or, in the Jerry Jones world, look up above to see what was going on down on the field.”
So, the idea was to provide a “spectacle,” and Up With People could do that with 500 people weaving, dancing and singing across the turf. "