Because it’s a brilliant business move. The majority of AP’s for any park / attraction barely get their money’s worth.
In California specifically, there may be a case for eliminating the cheaper local passes.
It’s like a restaurant offering free refills and then changing the policy because a few guests get too many refills. Stop wasting time worrying, the majority of guests are only getting 1 drink, it’s fine. If enough guests are getting too many refills then raise the price a little to cover your costs.
Ironically, I’m talking about a company who pays extra money per cup to install computer chips to keep guests from getting too many refills.