They had an episode where Homer dreamt about being Wario, so this makes perfect sense :)

It's probably because of "trunk or treating" which most of them are held BEFORE Halloween and in broad daylight because they're "safer" and "easier" and blahblahblah. Also probably because Halloween candy goes up in price every year.

While that may sound nice, it's not a pretty picture when you're a crazy ghost who gets his hands on a wishing star...

It's like Kinger said: The worst thing you can do in the circus is make someone feel like they're not wanted or loved 😔