I once worked for an extremely wealthy guy for a bit. He built a brand new office building and during setup I was in his very expensive looking back office... and I realized the nice and old looking books weren't even books... they were finely done hollow blocks of book looking replicas with real curved leather spines and everything...
I will never forget how that summed up the man to me. I quit not long after.
My grandma bought the last apartment of a new block, and to her surprise it came fully furnished -- with all the crap the interior designer had chosen. It had been the one on show.
The second bedroom was themed blue and black. I got about 30 new sci fi books, which had been chosen only for the colour of the spine.
Soviet book collecting was often form of conspicuous consumption - it demonstrated owner's ability to acquire goods - so book value was objective, established by society; while tsundoku seems to be driven by subjective value, placed by owner - making it closer to mild hoarding.
Not sure what the USSR has to do with anything here. People do this in America all the time, especially in the business world. It's fashionable to look like one reads books, yet people don't want to spend the time to properly do just that.
You should have a look at The Best of Myles by Flann O'Brien, and the stretch of items about his "readers", who will make one's newly purchased books look properly read.
Now I know they were Tsundoku practitioners.