Heads Of Beef / Klub Katz - S1-E11
Continuity mistake: In "Klub Katz" Courage spins his head once or twice. But when he puts his head back on it spins way over once or twice. (Like a thousand)
Continuity mistake: When Courage gives the chicken his suitcase, it at first says "Mars" on it, but then it changes to "Albany".
Queen Of The Black Puddle / Everyone Wants To Direct - S1-E9
Continuity mistake: When Muriel is crying she holding a big napkin which is purple, but when Courage tries to cheer her up it is pink, then goes back to purple.
Answer: Eustace is a rather two-dimensional antagonist character. He is just a mean-spirited man who takes out his hostilities on a vulnerable dog and resents his wife having adopted him.
raywest ★
I thought the reason had to do with the attention Courage receives from Muriel.