Keep in mind if this sytem is abused it will definitely change. Matter of fact the more publicity it gets the more likely steps to valide its use will be either added or more strictly enforced.
I work for Expedia Local Expert Concierge Services in Orlando, and I specifically handle groups and convention attendees with these types of tickets, there are several other types of tickets to choose from that Robert did not list, such as the 1 Day SeaWorld after 12pm ticket among others. You can purchase those tickets through me, and not have to worry about dealing with Disney's difficult ticket system for the convention tickets, as our tickets are printed hard stock and do not require dates and such. If you are bring a youth group of family reunion, I can also assist with special tickets for those groups as well!
Feel free to shoot me an email at firstname.lastname@example.org or give me a ring at 407-770-1953.