Is Ticket To Ride Asia played with stations?
Stations are specific to Europe and could potentially break (or perhaps make) games on other continents. Since Asia and other expansion maps can be played with both US and Europe base sets, the largest common denominator would be to not use stations in expansions. 

I have not tried using stations for Asia or India, perhaps it could be worth a test run, but I can see discussions coming up on combinations with Mandalas for India. Asia is more traditional in style (read: more like US) and tension remains mostly because of possible blockage by other players.