This "strategy" can hardly be countered with skill. You have to build mortars and pray that the Snipers get hit.
The problem of super resistant Snipers is even worse in 2v2s, where you can just hide behind your teammate, who also captures the map. One salvo from the Snipers will force away any German infantry unit.
It even occured that the Snipers got hit by a mortar and just one guy died, which means nothing.
Losing that one man of the Sniper squad should really hurt, but currently it doesn´t.
That is the point. Since the Russian sniper are two guys, they should be little bit more expensive due to better surviveability and on the other hand, if one guy get caught, it should be really hurting in the manpower with maybe 200MP for a replacement.