I think it would be safe to say that most AP holders visit the parks more than 5 days a year, most spread through out the year and not all at once.
so lets use your calculation. I have a premium pass at $649, I have been to park a total of 9 times this year. Avg money spent on food and merch would come out to $60 per visit.
so 9 visits would come out to DLR having to pay for 4 of them at $560
avg spent on food and merch is $60 coming out to a total of $540
so out of my 9 visits Disney loses a profit of.....$20
but you have to remember the more I go the less profit Disney makes...for instance
We are going up this weekend for my daughters birthday. so that would make my total to 10 trips; which would bring the total that Disney pays for my visit to $700. My avg expenditure still being $60 brings that total to $600
Therefore just for my visit alone it is costing Disneyland $100 to be there.
I'm sure if you could find out the amount of AP holders that have already been to the parks enough to pay off their pass, and avg the amount they spend (its already been stated by a few other AP's that they could spend as little as $20 per visit). Find the avg attendance of AP's that visit the park per day you will still come out upside down.
Heres how it could look.
lets say there are an avg of 1,500 guests per day that use an annual pas enough times to where its been paid off.
1,500 people multiplied by $125 per entrance = $187,500
of those 1,500 people there lets use the avg of $60 for food and merch (remember this is PER PERSON) so that would look like so
1,500 people multiplied by $60 for food and merch = $90,000 of revenue
so we get the totall of $187,500 for the total amount disney lost on ticket sales subtracted by the $90,000 worth of food and merch spent by each AP holder and you still come up short by....
$97,500 per day...