How do I prevent an item from automatically moving to a stock location after it is checked out from a shopping list?

If you don't want an item to return back to Stock location automatically when its checked out from a shopping list then go to Stock view, swipe left on the item and select "delete icon" from the side menu.  You will see a popup dialog like shown below. Select "Remove & Don't Auto Add" to set that item to not auto add to stock.