Incidentally, if you take the "challenge" offer and play 3 $1 BTCs - maybe at the start or end of a session while you are waiting for tables to fill up, you get entered as one of 20000 people in a $10000 all-in knockout - so in that case you are +EV unless you are losing a lot of EV to the field in push-fold poker - which I doubt.
At the moment I am logging on to PS every day, taking my net 20 cents subsidy and then going to play elsewhere. I did my 3 in bed on the tablet today
Basically this money comes from future dumb investors who need to be convinced PS has a winning new game format.