Its very simple why; as long as you can FOOL most of the people most of the time , you will make a good Buck

CO knows FT is but an extremely small population of the flying public and that the Vast majority wont have the slighest idea of what CO is up to

just look and you find time to time a newbie come along complaining hey why didnt I get UPed as a Silver when my EUA window came along there are empty seats in FC

so CO has no reason to spill its guts on how it has set everything up to Only give a free UP if they feel no way will they sell that seat even for TODs

and to do so at the very last min now at the Gate