Unlike musicians, game devs can not count with making money with concerts or any other live shows, their only revenue stream is what they can get for their games and piracy is a real issue. They just can count on people's good will, and in order to get enough funds they must understand how customer mind's works. Which is tricky.
I collaborate with a pair of game devs (Tlaero & Mortze) who only release completed games. One every 6-9 months, give or take, plus minor text-based stories for their patrons. From a creative point of view, they are more than happy as they have absolute freedom to do what they want the way they want. Financially, they are not doing that great, though, if we compare them with some other devs that release incomplete versions of their games 3-4 times a year. Considering they are longtime devs they have a pretty stable fan base, but I feel it still is considerably smaller than what their games quality and personal dedication deserve. And maybe that's because they don't include certain kinks that seem to be the most demanded out there (their games are pretty vanilla), but also because, once you release a completed game, people play it and that's just it, even if they know you're already working on the next one. The product is already completed and they can get it for free so there's no real incentive to keep supporting those devs after, maybe, throwing them the occasional one-time tip.
Patreon's model is, indeed, a double-edged sword, but I think the average patron like to feel they are part of the creative process. And watching how the game grows month after month, partial release after partial release, allows them to feel involved, more so if dev actually take into account their inputs (bugs, polls for minor details, etc). It's unfair, but I can perfectly understand (heck, I'm actually doing it with other devs I support) that odd mechanism: watching how a work in progress actually progresses leads us to be more OK with supporting it on a monthly basis (spending way more than the amount that could be its final market price) than being presented with a completed product you just buy/pirate once and then forget.