This event is not sponsored by Disney in any way. They do know that it takes place and go out of their way to make sure things run smoothly by having additional staff on hand and by assigning representatives to work with the organizers of the event to make sure that everyone in the park that day (both those involved with the event and those not involved) have a pleasant experience. Disney's involvement in it isn't really any more serious than it would be for any other event that brings a few thousand people as a group into the MK... As for the shirt thing, DIsney does not sell any merchandise for this event. They remain neutral with it for the most part. Where you might have gotten confused is with the red shirts that participants in the event wear to signify their connection to it. If a regular park guest shows up in a red shirt and feels uncomfortable, Disney will give that guest (at no charge) a shirt to wear.
