Actually, I'm pretty sure Winter Park started the season pass wars. Vail obviously has taken it to an extreme, but they had to compete with the other CO resorts first.
"...The 'pass war' began in 1998, when Winter Park dropped its season-ticket price to about $200. That move pushed other resorts to do the same or lose market share.
"In 1997, for example, a season pass for Keystone, Breckenridge and A-Basin cost $750. Winter Park’s season pass cost $600, and Copper’s cost $595...."
http://www.denverpost.com/2007/09/07/ski-pass-cost-comparison-softens-lift-whines/
Here is another interesting article:
https://www.washingtonpost.com/arch...unt-war/3539ac1b-b09c-431d-8c31-3251b514e862/
The chapter in the Colorado season ticket wars I most remember happened back in the late eighties, early nineties. That was when every year I got a Summit Pass (or whatever it was called) that included unlimited skiing at Copper, A Basin, Keystone and, I believe, Breck: can't recall, but probably also Winter Park - all at a single, reasonable price. That's the pass I still wish I could get.
In practice, back then I'd only ski Copper, A Basin, less than a half dozen at Winter Park, and a few at Keystone and Breck (in a sixty to around ninety-five day season, for me). The best.
A big deal, at least for me: having A Basin and Copper on the same cheap season pass was a big deal.
Then Vail bought up the competition, including A Basin, Breck and Keystone, and that pass ended. And prices rose.
I understand the split up season passes increased in price for a while, but my memory gets fuzzy there. I guess until the above mentioned Winter Park move in the late nineties.
(Note: For monopoly reasons, Vail had to free up A Basin, but kept a relationship with them through the Epic Pass.)