In the back of the main gift shop at the Wilderness Lodge, there is a mini-convenience store. The selection is not large, but you will find some basics like milk,
juice, eggs, bananas, butter, yogurt, cereal, dry pasta, canned soup, a loaf of bread, sliced
cheese, soda, etc. There are also snack items for sale as well as beer and a small selection of wines. For my family's tastes, I'd be able to find
the makings of a basic breakfast or lunch there, but for dinner I'd
need another source of supplies.
To get fresh meat or veggies, you would need to rent a car or take a
cab if you wanted to visit a grocery store. Another popular alternative
is to arrange for a grocery delivery. You can read more about this
HERE.
Have a great trip to WDW!