That was because the people were allowed to fly with a "guest", and started selling their seats to strangers in violation of the rules.

With this airline, everyone will be required to buy a membership -- no "guests".

Also, this seems to be month-to-month as opposed to a lifetime deal. "Unlimited" for a month could be true. "Unlimited" for life isn't.

I wonder how the duration-limited "all you can fly" JetBlue deals worked out for them.

"Unlimited airpasses" for international visitors to places like Southeast Asia are pretty common, combined with long-haul international flights, too.

No, there are guests allowed. I asked if I could fly someone to visit me instead of me going to them, but the account manager said I had to accompany all guests. =\ Understandable, but less useful for me.