Not completely false. As an LTS member, yourself, you should understand that you get 500 "free" Zen each month. You can also get "free" Zen by doing various surveys on the website. I have sold my "free" Zen for Dilithium on occasion - and I'm sure I am not alone there. So while it is true the vast majority of Zen is paid for by someone there is also a percentage being sold in the Dilithium Exchange that was never purchased by anyone.
That is not really free though. In return for paying $200-300 you get $60 worth of "zen" a year. That stipend might be cheaper than buying it outright averaged over the life of the game, but it is hardly free.
Also, surveys are not free either. Market research is expensive. You are selling them your demographic data, which is a valuable commodity, in return for in game currency.