Free dining is absolutely related to it. I've talked with the managers, and they absolutely hate the dining plans. They only get a portion from each person, and for the more expensive dishes, they barely break even. Some have had to go to lesser cuts, and some, like LeCellier, had to go to 2 credits.
It's not even free dining. Ever since the advent of the Disney Dining Plan, food quality (both TS and QS) and portions (TS) have declined while prices have increased at a not-proportional rate.
Remember when the Dining Plan included gratuities, plus an appetizer and dessert? And there were slow times at the parks? Ahh... the good ol' days...
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My neighbor used free dining on his existing AKL reservation this morning. He had to pay for park hoppers and rack rate, but that was $820 additional compared with the $2200 he'd have paid for the dining plan, so he came out ahead.