I buy one every year! My reason is a little different because I frequent a lot of boat launches controlled by NYS parks. We also camp at the parks. However, I "believe" that if you have camping reservations and show your printed receipt at the entrance, you do not need to pay an entrance fee.
If you do want to purchase a pass, keep an eye out on Black Friday.... they usually run some kind of deal for online purchases of passes for 1 day ONLY!
Bottom line, though, if you're only going to be in a couple parks, you're really not going to get your $$ out of it.
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