Somewhere in those posts Heat made a good comment that I think gets overlooked by many. He mentioned something I talk about alot and that's networking. Making friends and getting to know people is how I find most of my hunting spots. When I get invited to a place I remember that and repay the favor sometimes with "gifts" like beer, shells, buying lunch, driving etc...and sometimes by inviting them on a hunt.
Buddy of mine has a prime dove spot I make sure he knows I appreciate him letting me hunt that spot by giving him some things as well as inviting him on some duck hunts later in the year.
But I spend a lot of time talking to people about hunting, where they go, etc. I serve on my local DU committee...I go to a lot of DU and Delta events. It takes effort and time to build relationships and I can see how for some it might just be easier to just pay and that's fine.