My most recent case: I went on holiday to a resort in Turkey, numerous Russians, families, retired, etc. I don't pass as a Russian-speaker (but I understand quite well) and once they hear me talking other unrelated language they naturally start to speak more freely in front of me (i.e. more liberal use of swearing, and even slurs if no other Russians are around).
While sunbathing, or at the restaurant, or the pool, they were talking about daily, mundane things, same in the restaurant, etc. But when floating in pairs 20-30m from the shore? Politics.