OpenAI said it will allow users in the U.S. to make purchases directly through ChatGPT using a new "Instant Checkout" feature powered by a payment protocol for AI developed by Stripe.The new chatbot shopping feature is a big step towards helping OpenAI monetize its 700 million weekly users, many of whom currently pay nothing to interact with ChatGPT, as well as a move that could eventually steal significant market share from traditional Google search advertising.