I am not conspiracy theorist, but if the payout was $100+, then most people would likely withdraw that amount. Meaning thousands of people would withdraw at the same time. So PokerStars would lose that money.
However, if the prize was a small amount, people are more likely to use the money to play = more rake/activity for PokerStars.
This is the case 95% likely, however the jackpot money is never PokerStars'es money, it's always players generated money. The Deal is 100% zero-sum game, Stars just rakes it like it does for poker. Obviously still this is 95% likely what happened, they want as many players as possible to get share of the jackpot so the money is not significant enough to withdraw so winners play more and rake more. And to provide to players who are losing something extra so they play more.
This is why it's daily resetting tickets and can be won twice everyday. To maximize everyone's place in 12 hour window.
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Then there is 5% chance that PokerStars themselves simply don't understand the rules of the Deal. I tried to contact their support multiple times after September 13th when it re-appeared and holymoly I gotta tell you. The support staff kept making comments like, "players who played it last 48 hours", "more quantity of players the more money too".
They did sent some of my stuff to ideas and complaints departments and promised to email me within next day. No email the next day so I contacted them and livechat support told me they have refused to email me back "because I were ridiculous" so it's hard to say whether they were dismissing me because of guilt, or whether are on the similar understanding as the support staff I talked to.