I didn't word that right - I think there are a few quick-service places you get a discount with the TIW card.
Yes! The food courts at the value resorts and most of the CS places at AK accept the TIW card. I believe the CS restaurant at SSR and the restaurant at the WWOS accepts it as well. In addition, because they are counter service, the 18% gratuity is not added. Don't forget, the 20% includes any alcohol as well so that Lapu Lapu or bottle of wine is also included in the discount.
We had a family meal at O'Hana one night...7 adults (one was 10 though), 5 kids and one infant...and 2 TIW cards between the 13 of us. Our tab alone had 5 Lapu Lapu's on it

. My sister's family of 4 and my family of 4 were on one tab and our bill was $315 before the discount. The TIW saved us $63 on that one meal

. Since we were a party of 13 (one party of 5 and one party of 7 + an infant), the 18% gratuity would have been added automatically anyways because of our party size so the tip would have the same amount either way.
We used the card(s) on our family meal at Chef Mickey's (dinner), LeCellier, 50's Prime Time Cafe, Boma, Sanaa, Pizzafari, and Olivia's. It *more* than paid for itself on just that one trip. I'd actually bought it in 2011 for our F&W trip and only paid $75 for it. Even at $100, it would have been a great deal.