Hi, Richard!
The Hess gas stations at Walt Disney World have been replaced with Speedway Stations. I really like the change, as Speedway Stations are what I use in my hometown so I am familiar with them. There are 3 locations to choose from: Magic Kingdom area (World Drive), near Disney Springs (Buena Vista Drive), and near Disney's Hollywood Studios (near the Boardwalk).
I cannot tell you much about the Speedway by
Disney Springs, as I have not been there. The station near the Boardwalk has very limited selection, basically sodas and chips. The location near the
Magic Kingdom is much bigger with even some hot food options, I think I even saw someone getting a pizza there last time, but that can always change. Call ahead to them to make sure they have the items you need.
You might want to check-out what your resort has to offer in its gift shop. Most Disney resort hotels will have the basics such as milk, bread, snacks, muffins or doughnuts, and other general items. If you are staying a location with a full kitchen and need a full complement of groceries, you may want to check into a grocery delivery service such as the Garden Grocer. For a fee, they will do all you shopping and deliver it to your resort. Check their website for details and pricing.
I hope you find plenty of goodies to keep everyone in your travel party happy!
You can take snacks and drinks in the parks, so toss in some crackers or juice boxes so you can avoid lines and save a few dollars.(no bottles or alcohol, small soft-sided coolers only.)
Cathy