You really don't have to use all the credits for table service for the deluxe plan to make sense. The breakever point on meals alone is about 2/3 table service, so if you want 2 sitdown meals per day or a signature dinner each night, the deluxe plan would be the way to go.
And you really don't have to be a big eater to spend $72/night on food at Disney prices! I'm a compulsive overplanner and I run the dining plan numbers through my spreadsheet before every trip to decide which plan makes the most sense. Some quick meal prices from this year's sheet (including appetizer, entree, sometimes dessert, drink & tax):
Narcoosees - $87.33, $87.14, $78.81
California Grill - $78.81, $69.93, $59.64
Artist Point - $61.77, $62.84, $58.58
Spirit of Aloha - $58.56 per adult
So for a family like mine that wants a signature dinner each evening and considers steak, lobster, sushi and such as much a part of the vacation experience as the resort pool, the deluxe plan really is a no-brainer. Even if we get the cheapest possible CS lunch (which we never do - I HATE the whole CS experience of waiting in line, hunting for a table, getting your own condiments, no drink refills, etc.) and use our snacks for fruit and bottled water (which we do often), we'd come out ahead on the plan.