Of course it wasn't as expensive in 1996-97 as it is today. The point remains that the producers went out of their way to make various price categories that would be accessible, instead of making everything $80 (or whatever it was at the time). As I recall they even had an ad campaign for a while that was something like "$20, $30, $50, you decide."
And I did know Rentheads that did the rush multiple times, and then also received full price tickets as gifts for more shows. Did that help the box office business? I think so. Would they have been able to do it if the tickets were all full price, or even TKTS priced? No.