Yes! Not 100% sure but I have seen coffee in the start area. I would assume bagels and a few other breadstuff type things along with coffee, tea water ?
The bakery will have a stand open in MK with a few things available. Again having run for 11 years not 100% sure....neddless to say that there is service in the park.
My parents like to drop me off at EPCOT and take a nap in the car. Then they hop on the monorail and head over to the MK to grab something from the bakery on main street while they wait for me and the rest of my running team to come through.