Yes there are offroad contests in many countries besides Russia, but how about Russian off-road? Have you seen it? It differs from the mudding in other Western countries greatly because there are so many places suitable for this fun that can be accessed just by stepping out from the paved road. See it yourself. The one above engages only Russian UAZ cars.
And in this one guy tries to crawl on his car with it almost under water:
And that’s some more heavy Russian off-road four-wheel mudding: