because bill gates is a creepy bridge troll who giggles about controlling the population and uses slave labor to make destructive software designed to fail and cost you hundreds of dollars every few years.
Fax. Developers which can't accomodate for systems other than Windows are either lazy and incompetent or have some weird ideological gripe that makes them think that even though they are indie developers they need to follow some big corpo dogma of putting all your eggs into windows basket.
i disagree. most people use windows, so it's only natural that most indie devs make their games for windows. it just sucks when i see a good game like this that requires me to give up my privacy to play.