Correct me if im wrong but Joyetech who makes eVic is chinese company. I boubt that anywhere in the world (including china) there are as much mac/linux/unix/whatever-else users as there is in the USA. Still most of the people use windows and thats why its made for windows as #1 . Ofcourse, for their own good - they should add support for other operating systems also soon but still you cant give a negative "score" for that just because you dont use the most "used" OS in the world.
Would be same if i would move into USA and take my car with me and then start to yell that theres no spare parts for it in US

I have 1999 BMW 730D (yes, diesel) what never was in sale in the US.
Different countries - different people - different usage of devices.
Maybe littlebit confusing speech because english aint my first language.
Just checked - eVic is sale in here for 100€.