They could have achieved the same without any license keys. Just a "Purchase" button along with an "Already purchased" one. You make the ethical judgement as to which one to click. The purchase page could have a few suggested prices along with a pay what you want option, one time and recurring.
Also I'm not too sure why FUTO are allergic to the term Donate. There's a whole generation of people who got taught how it works and what it does by Wikipedia. Slap a funding bar with a brief explanation for what it funds, add the donation options and everyone would know what's it for and why they should donate if they can.
Anyway. Purchased the thing and I'll keep supporting them till it's GPL.
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