The only things you pay for are the games that dispense tickets for prize redemption, the completed versions of the artwork you make (or the Cyberspace Mountain ride video)in the Create Zone, and FoodQuest.
In my opinion, the FoodQuest food court (which is operated by The Cheesecake Factory Express) is absolutely the best value on WDW property. Prices are comparable to the theme park burger-n-fries, but the quality is much, much better. The portions are large enough to share, as well, so two people can get a light lunch for under $10.
If you have a UPH, I think it's worth it to stop at DisneyQuest just for lunch. Be warned, however, that once you enter to get lunch you'll find the place is so fun that you may stay until they kick you out at midnight.