Maybe this is another way to force people to shorten their park days. Let's say you will not eat Disney food. So you might still go, maybe pack a protein bar which would probably get past the gate, but then have to leave to go eat a meal at some point, maybe six hours later or so, assuming you ate a good meal before going.
Maybe they are trying to cut down on the people who come to the park from morning to close and who don't make at least one ADR or QS meal. In other words, the Disney meal is the price of staying the whole day.