I've never heard of lifetime passes for sale. I'm pretty sure that when the 1,000,000th, 5,000,0000th, 10,000,000th, etc. person stepped through the gates, he or she got special passes that may have been lifetime, but I'm not sure. I know that the people who got Annual Passes during that first year of operation get "Charter Member" rates for AP's every year, which I believe is better than FL Resident rates (I don't know if Charter Member FL Resident applies ).
This is true. I don't know if they were as cheap as $100, but they were very nicely priced, and did last forever. My neighbors were there when they were offering them, but passed because they were low on funds at that point in their lives. But they are kicking themselves, I assure you!