Continuity mistake: At the arena, when Scooby's blue suit bursts, the ground is covered in small blue pieces that disappear in the following shots.
Continuity mistake: When Hawk is launched against the rocks he makes a square dent on the rocks. A shot later it's a roundish dent.
Continuity mistake: At the beginning of the movie, when Scooby escapes with the meat, a cop catches him while standing next to a sunglasses stand. Watch as Scooby manages to roll away from him - the distance between the cop and the glasses stand changes.
Continuity mistake: When Simon Cowell arrives at the table, the ketchup bottle disappears in the wide angle and reappears in the close-up.
Continuity mistake: During the whack-a-robot game, a big chunk of the broken robot lies on the counter, but it disappears a shot later.
Continuity mistake: Scooby and Shaggy just met; during their first encounter, the sandwich changes position without being touched, multiple times. (00:03:30)
Continuity mistake: When Fred watches the burning van he grabs the spare wheel cover and dusts it off with his hand. A shot later his hand is spotless, but a shot later he paints his face with the soot that was supposed to be on his hand.
Continuity mistake: When the movie ends and they all see the store front, in the Spanish release it is all written in Spanish, but a shot later it appears in English.