See, I don't know if its just me or what, but technically an underground model for a Purchased Jailbreak "could" work.
We just have to use some other names for the Jailbreak community and it kind of makes sense.
Saurik could be "Apple", or....in this case more appropriately "App store"
Jailbreak tweaks could be "Apps", with both free and payed apps, and ad supported
and Jailbreak team could be just "iOS development team"
Here we have the iOS development team being paid (in part originally, but we have to modify to fully) by proceeds from the App Store, minus the costs of running the app store and its servers (repos). The devs would split their earnings by 30-70, with 30% going to the App store. This cuts into the profits of devs, so lets add another layer where the user has to pay to use the app store. This way we don't have to rely on donations to power iOS Development, there could be dedicated jailbreakers due to the income, and users get a faster/easier/stable jailbreak.
I know its not very likely, but think about it, this way we could pool our exploits by actually buying them from devs (causing sharing of resources), have a faster, more resourceful Jailbreak team, and people who want to jailbreak, just pay for it, leading to less pirates (as we know they won't pay for it, because they could have just gone and bought the original apps), and most of all it would be a regulated and stable community......
utopia anyone?