Other mistake: Dorothy said she's never had a mink, but her mink stole was stolen in the Break-In episode. It was also in the pilot episode when Blanch asked Dorthy if she could borrow her mink stole.
Other mistake: In the opening scene showing the outside of the house, the garage and driveway are on the left side of the house. In "End of the Curse," the girls raise minks in the garage, which is accessed from the back corner of the kitchen, thus the garage is actually on the opposite side of the house. Furthermore there are four large bedrooms and at least one large bathroom down the hallway. The hallway shoots off the living room at an angle. There is not enough room to fit all those rooms between the supposed garage and the kitchen and the lanai; all of the rooms would overlap one another. Lastly, the lanai seems to be surrounded on three sides by the house (as is typical of a lanai) but the hallway leading to the lanai, and the way the girls enter from the left, would put it on the very front corner, and surrounded by nothing.
Answer: Ice makers were a new invention, advertisement purposes.