"Why would POLISH media types NEED to be filming Russian troops inside RUSSIA???"
They were not accused of filming troops. They were accused of filming "without permission in the region of troops stationing in North Caucasus". In other words they were found with cameras in a region where the Russians were doing something suspicious.
By the way, why should German, British, French, Italian journalists film American troops in Iraq? Maybe Americans should arrest hem?
Well, the German, British, French journalists obtain permission prior to filming - if they haven't they'd be detained and expelled from the region.