At Tuolumne you'll certainly find enough food to supply yourself through to Red's Meadow, especially if you're not picky.
At Red's Meadow they do have a fairly well outfitted store. But it seemed like a lot of the backpacking food from either people who left it there or from buckets that people never picked up. There was only one or two of a lot of different things, chips, packs of cookies, Mountain House dinners, etc.. We planned to resupply on lunches and snacks to get through to Red's. In the end, we could have bought everything there, including dinners and breakfasts, but we just may have been there at a time when they had a lot to pick from. They even had "Packit Gourmet" dinners and lunches. This is why I think some of the food was from previous backpackers, I don't think they normally stock food from "Packit Gourmet." They had a selection of fuel, but since we were using Clean Strip Green Denatured Alcohol, and had all we would need until we got to Muir Trail Ranch, I didn't look at it very closely. They do have single, zip-lock filled detergent packets for sale and have a laundry machine available, which we took advantage of. They also have a lot of first aid supplies and camping gear. I would liken it to an RV campground store, with the addition of some backpacking food and gear.
At Muir Trail Ranch, you'll be depending only on food that was left by previous backpackers or from buckets that were never picked up. They had a ton of oatmeal and nuts. And a lot of candy and snack food. They had a fair amount of freeze dried dinners and a lot of home-packed meals of who-knows-what. I remember a lot of Asian packaged food and candy also, but I couldn't read it to figure out what it was. If you're not picky you could easily find enough food to last through the rest of the trip, but I'm not sure how sympathetic they are to people who plan it this way. Our bucket had not arrived when we did so they urged us to rummage through the buckets to supply ourselves. We were pretty disappointed at this prospect, especially after taking the time and expense of sending a bucket. But, by afternoon, our bucket arrived so we were ably to put back everything we scrounged. It was also very easy to send back home everything we weren't going to need for the rest of the trip. Their store is limited to MTR clothing, a selection of first aid items, and an assortment of camping/backpacking supplies. They also sell fuel, but it will be limited to what they have on hand, you can't count on them having what you need.