The big, televised "Christmas Day Parade" is filmed over several days in the Magic Kingdom. The dance numbers are performed multiple times, and filmed from many angles. Floats run down the parade route sporadically. They stop and start, waiting for weather, cameramen, the planets, & a bazillion other factors to align. Celebrities tape their segments out of order, all over the park, and the whole thing is edited together and sent to the ABC network for airing on Christmas day.
The year I witnessed the taping (I was not in the audience), people who want to see the parade arrived at the crack of dawn and waited in a separate line to enter the park. They somehow had been told in advance what to wear. All the spectators were wearing red and white, and Disney gave them red and white pompoms and flags to wave, presumably so the audience would look great on camera.
Viewing areas for the parade were strictly roped off, and the audience was guided to their specific viewing areas, where they stayed for hours and hours. The rest of the rif-raf (like me) were not included in the viewing audience areas, and CMs politely but firmly directed us along passages out of sight of the parade route.
There were no photopass photogs available that day on Mainstreet, and you couldn't stand anywhere within site of the front of the castle, though you could go around the park to the backside of the castle in Fantasy land. The castle itself was blocked with screens, to hide the dancers and crew who were filming all day.
The Christmas parade that year captured and promoted the "High School Musical" phenomenon, so everything conveniently color coordinated with the red & white Wildcats dance numbers. (One wonders if even that was planned?!)