It's the same pricing on Patreon. Soon it will be $5, and eventually free when the next version releases....but once you pay at whateer tier here, you own it.
That's just the way they make money, a lot of them are not on Steam, so this is a way to make some money, and well...
They may have ridiculous marketing, but they make ridiculous money
Graphtreon: Patreon Earnings + Statistics + Graphs + Rankings