1st gen Apple Pencil cap

So I have lost my apple pencils cap that covers the lightning cable and the pencil is still under warranty. Despite this it would cost me $16 to get a replacement from apple. Why are they charging so much for a piece of plastic with a magnet in it that’s smaller than my thumb? Like realistically it would cost apple less than a dollar to manufacture this part of the pencil so why are they charging $16 for it? I would be willing to pay anything under $10 for the product but I don’t understand the need for them to charge over 500% more than the cost to manufacture?