I'd say it's the same all over the world, ea. the weapons that the country in questions army is mainly using is common in the airsoft community. if in produce.
as for the question: I see them every now and again, but not too commonly, no.
Then again, two of the four common weapons are being used by UK police (etc). The other two are the two are ´the most common assault rifles worldwide.
...is g36 common in countries that does not use it? the only other reason for having it, because its not very attractive, in my eyes, is that it seems quite practical..