That's legit. You can definitely tweak a Windows app to run well in Wine. I'd love for every game to have a Linux version but the market is tiny and most of these indie studios are maybe 3 people max working on the game. I don't think Linux users have a realistic expectation if they are strictly waiting for Linux native versions without paying to support this. Despite the brilliant art that is this game, I'm pretty sure Lucas Pope was looking to make some money off it.
Pretty much everything I've tried lately has worked perfectly through Wine.
I have even less reason to care strongly about a Linux version as I often use OS X. I want either all three platforms or just Windows, but working through Wine.
I've stopped being quite so idealistic. If it's DRM-free and runs on Wine, I'm satisfied.