When Lefty's partner Red Watkins enters the café, he has no moustache. In all of the other stock footage scenes he has a pencil-thin moustache.
When Shemp scrams through a door upon discovering Angel just behind him, as Angel strikes with the butcher knife and hits the door frame, another cut in the frame from a previous take can be clearly seen just below the knife.
When the Stooges and Gladys are at the door you can hear them talking, but their lips aren't moving.
In the original short (Shivering Sherlocks), Gladys (Christine McIntyre) owns the Elite Cafe and takes on the Stooges as workers, where they later stumble across the armored car robbers who are living on the property she is hoping to sell.
In this remake of that short, the Stooges run the cafe, and while chasing one of the crooks, Gladys simply walks into the diner with no explanation as to who she is or what she is doing there.