Before the Stooges flip their wives over, the hat that Moe is holding disappears.
When the Stooges burst through the front door of the mansion, you can see it is actually opened a little bit, already.
When the guests pile pies on Moe Howard's head, you can see Dorothy Appleby could not do it because she could not see due to the pie in her eyes, so she put the pie down and waited until everyone else finished.
Under the newspaper picture of the 3 Stooges it has a caption that says mushroom murder gang but the announcer at the hanging calls the 3 Stooges the mushroom murder mob.
The saws which The Three Stooges are using on the bars are wood saws, which would be useless on steel.
When Moe runs the saw across the top of Curley's head, if you look closely , the saw is not damaged at all . Its only when Moe raises the saw in the next shot that you see that the saw teeth are bent and crooked.
When Curly climbs the tables and chairs that he stacks to reach the top bunk, it's a stunt double. He keeps his head down so his face can't be seen, and the hair on his mostly shaved head is darker than Curly's.
It's never explained how the 3 Stooges know where to find the girls that they married.
Some of the pie that hits the lion hunter in the face, drips down onto his mouth, causing Eddie Laughton to flub the word "wounded".
That's what makes it so funny and realistic is thar the lionhunter got hit with so many pies, he couldn't speak correctly.