Everyone asking 'why', this excavator is not really an excavator per se - it's a recultivator, used to distribute and tamp down fertile soil in a former open mining pit.
It's not 'Soviet wastefulness'. USSR excelled at small-series production because of vertical integration of design & manufacturing. The Antarctic vehicles below were designed from scratch and manufactured inside of 3 months.
https://youtube.com/watch?v=f6R-h06IsJw…