Whenever I see people playing DCDF, I am worry them, yes I maybe a little extra, same players probably making good profits from there? Frankly speaking, if player complaint non-progressive games difficult to play, how RWS makes profit from DCDF which gives away 1-2 grand prizes at $70K+ a week and 2nd level progressive price range $1.5-$3k a few times a day, never believe a casino will do "charity", the only possible reason that RWS can make profits from DCDF is they adjusted the payout percentage to the lowest where they actually creates 1-2 big winners weekly and these big winners will eventually contribute the fund back to the pool. The theory is the same as FFF at MBS, the major prize releases every 15-30mins ($5k-7k) during peak hours creating 1 winner from the 120 sets of machines and there are actually more than 100 players contributing the fund to the pool, or might just straight forward to say there are actually more than 100 losers.
I think the casino doesn't purchase the machines, they purchase the software (games). Machines can be reloaded with any games released by the same manufacturer, if the games happened to be unpopular, the casino can purchase new games and reload to the machines or return them with the unpopular games to the manufacturers. I believe the software is far more costly than the machine because the machine is basically just a PC wrapped in a cabinet with a note collector, it basically cannot earn a single cent for the casino if there is no game loaded into it. As for software, they involve idea, graphic design, theme, trend, market needs, etc... and that's why I think software copyright is more costly than the hardware.