Hunting & fishing licenses pay the bills for many free outdoor tourism attractions.

As anglers and hunters drop out, DNR seeks more sustainable funding | MPR News
https://www.mprnews.org/story/2021/12/14/as-anglers-and-hunters-drop-out-dnr-seeks-more-sustainable-funding

And that doesn't count that some organizations such Duck Unlimited or, going way back, the Boone and Crocket Club (charter member: T Roosevelt) were large non-governmental conservation organizations.