Consequences of adding all items on Amazon in the cart?

I was talking to a family member where they wanted to order a lot of goods from a website. I jokingly said I'll write a script to add all the items on the website to the cart. What would be the consequences if one were to write such a script? I know of one off cases were one item was priced in millions. My understanding is that even if one were to order such a highly priced item, the payment processor wouldn't let it through.

Edit: I do NOT intend to do so.