This business model is cool, free game digitally,
but boxed it costs money.
I suspect this is mostly a hobby for him.
A friend of mine runs a small music label in Italy ( https://www.heavypsychsounds.com/ ) in the stoner segment and had some success printing vinyls in limited edition of the bands he publish
You have to create your fan base first, but usually when you build it from the ground up it's loyal and buys everything you print
He makes enough to sustain a small business and had the satisfaction of getting in touch with the bands he once listened to when he was younger and to republish them (Nebula, Nick Oliveri from QOTSA, Brant Bjork from Kyuss)
BTW in this specific case the bands get the full cachet for the live gigs and the merch they sell at the venues, the label pays for the pressing and gets its own share from selling the records and from the merch sold on the label's website
It's a small business, not a shady multi billion company
it's made out of passion, not for greed
many small indie actors, few giant ones
minecraft was created by a single developer, angry birds costed officially around 100K, both made hundreds of millions
putting up a band that sells records in the tens of millions doesn't cost less than making angry birds
and it's harder to get to that point, band that sells so many records are just a few
For example Lady gaga sold globally less than 9 millions records, Angry Birds has exceeded 12 millions
It's like with music or movies or novels; you're taking a huge risk by quitting your job to do it full time. The sad thing is that it was only a few years ago when it actually did make some sense to try it.
(Keep in mind that 150000 EUR might be "beer money" in the US, but the typical German salary for a non managerial SW engineer is around 60000 EUR, so 150000 EUR are 2 "good" man years' worth of money).
It's more of a "feel good" symbolic support model, and that's great! There should be a place for that in our lives too.
Being paid for working on something that ultimately isn't about the money is actually a really tricky problem to solve, and this feels like a decent approach.