Right next to the gift shop and trail head is one of the two dining options in the park. This is a little snack bar that offers about 5-6 options (hot dog, hamburger, chicken sandwich, etc.) The prices are fairly reasonable (similar to fast food) - the chicken sandwich came with potato chips and a pickle for $4. They'll heat it up while you wait in a little picnic area. This isn't fine dining, but it's a reasonable option if you're in the area around lunch time.
It's the only restaurant in the area -- the closest restaurants would be in Davis -- but the food is good and the prices are reasonable. You can't beat the convenience.
The restaurant is on the main floor, as is the gift shop and the conference facility. The rooms are on the second floor (the stairway is just to the left (out of frame) of where I stood when I took this picture). The front desk of the lodge is just to the right (also out of frame) of where I stood.