If you're going to buy the passes and play the game, at least just buy the daily ones, and only on the weekends at the busy trailheads (maybe about only 25% of where I go anyway). The reason is that that is what is "Demo" about the Demo program in the first place. They want to see if they can scare enough of us into becoming trained into going down to REI or wherever and purchasing annual passes. This is their ideal as it requires no one at the TH to sell it and is easiest to enforce. Their least favorite idea is to have to sell individual passes because it is more confusing, requires more paperwork, is more labor intensive, and will require more employees devoted to selling and enforcing them. By buying the annual pass you are giving in. Unfortunately I think they predicted correctly that we would all line up dutifully at REI and buy them every Spring because we would prefer to avoid hassles, and maybe save money (not for me because outside of the most popular TH's enforcement is pretty sketch). Really if there were no annual pass sales, and only those flimsy day things out there you would see this program wither away. I've seen plenty of people reuse their old day passes, just change the dates or make them totally illegible.