Moving ingredients into different aisles from the Shopping List is easy.
For the Web:
Open the Shopping List by clicking on the icon in the upper right-hand corner.
Hover over the ingredient you want to move, and then select Change Category.
For iOS
Open your Shopping List and make sure you are in the "Aisles" view. Find the ingredient you want to move and click on the item in the center of the ingredient name. Click Edit, then Click Category. You can also long click on an ingredient to move it around.
For Android:
Open the Shopping List and find the ingredient you want to edit. Swipe the ingredient to the left. From the small menu, choose "Edit Ingredient" and then select Category.