Yes, they have at least one band each day, dependent on the time of year, of course. I would think they don't have many from late June until September, but I have had groups marching there every other month, and we have never been the only group. There are some days in the midst of spring break that they will have 3 bands march mid-morning (not associated with any Disney parade), then 3 before FOF, and 3 before the first MSEP.
I am very impressed with the Disney Performing Arts CMs. I have had marching bands march at the MK and Epcot, concert bands, string orchestras, a handbell choir, and choirs perform at DTD and Epcot, a musical theater group have a clinic at Saratoga Springs, and many different types of groups (jazz bands, concert bands, dance groups, etc.) do various clinics backstage. The CMs are unfailingly enthusiastic and knowledgeable. It's a great experience for student performers.