Chechen war was a special story, Chechnya is a really dirty area especially in the springtime, they have no good roads and the war was 15 years ago. At this times russian army had almost no money, it was uncoordinated, inexperienced soldiers etc., they had other worries than staying clean.
You should see more videos from modern "battles", for example from South Ossetia, in this short war the russian army looks as it should be, pretty clean and normally.