Lou, I'll answer your question by repeating a post from Bob Jewett from earlier in this thread, then I'll add a concrete example to show what is going on.
EXAMPLE
Prize Fund
Assume that the number of entrants for one of the main 3 events is 500. The prize fund for each of the DCC's 3 main events is equal to $150 times the number of entrants plus $25,000. So with 500 entrants, the prize fund will be 500 x $150 + $25,000 = $100,000.
The $150 per player comes from the basic entry fee of $160. A $10 "registration fee" is part of that $160, but that $10 does not go into the prize fund.
The $25,000 is what DCC calls "Guaranteed Added" money. So that amount is part of the prize fund regardless of the number of entrants. If only 100 people entered, the $25,000 would still be in the prize fund. DCC bears that risk, as slight as it may be. [And if the entrants fell way off like that, we would certainly see some future adjustments to the finances.]
Buy-Backs
I have counted the number of players who enter, and the number who buy back, for each event for many years now using the "Completed Matches" lists (that's not a fun job). The percentages of buy-backs I have seen for an event have ranged from about 60% to about 80%, with two-thirds being a reasonable overall figure for all 3 events over those many years. Each buy-back now costs $60. So, for the example here, and assuming that two-thirds of the players bought back, the buy-back money would be 500 x (2/3) x $60 = $20,000.
Total Player Entrance Money
Counting the basic entry fee of $150 per player, plus the "registration fee" of $10 per player, plus the buy-back money (which is essentially another entry fee to continue playing after the first loss), the total money paid by the players in this example is 500 x $160 + $20,000 = $100,000.
Added Money
How much, then, is the added money for this example event? As shown above, the prize fund is $100,000 and the players paid in a total of $100,000. So, in the true sense of added money for any event being the excess of the prize fund over what the players paid in, added money for this example is zero.
But DCC views it differently, at least publicly. The "registration fee" is not added to the prize fund, nor is the buy-back money, and DCC then provides $25,000 in "Guaranteed Added" money. So what happens to the players' money that is not added to the prize fund? I think it is reasonable to view it as just part of DCC's overall revenue from the event used for their untold expenses of putting on the event. One such expense is the $25,000 paid for Master of the Table prizes. Another is $16,000 added to the prize fund for the Bigfoot event. Another is money added to the Banks ring game. I don't know whether they contribute anything to the Mini's, although any added money for those is said to come from "outside sponsors."
The DCC has, of course, many expenses other than the prize money in the various events. And they have other sources of revenue. How the revenue compares to the expenses overall, I have no idea. In an interview years ago, Greg Sullivan said he lost about $100,000 on the first three events (combined). I imagine losses have not been the case now for many years.