No surprise seeing as you need around 2000$+ worth of them for all 9 Tier 3 pieces +Reagents. People don't want to do 5000+ Naxxramas Scholomance and Stratholme runs to barely get 3 sets let alone all 9.The whole system for tier 3 i a scam perpetuated by blizzard and wow tokens being as high as they are is due to the above in my opinion seeing as there is nothing else in the game as of right now that warrants the token to get this high.If you can debunk this go right ahead. As it stands here is the culprit.
I miss mission tables where I could easily make few mils a month just by logging in.