is it possible? i don't really feel like removing all of them one by one

;; you can go to the side and select the highest amount from each item to remove as a mass. but there is no quick 'remove all' function for the shops.

Unfortunately, there is not a way to remove every last item from your shop all at once and have them all end up in your inventory. You can, however, remove as many of a specific item as you want to. Deleting a shop will also delete every item in there, but you will not get the items back and they will be gone forever.