How should customers pay when using a shop?

Explain in more detail why there shouldn't be a shopping cart; perhaps a solution can be found.

I can't quite imagine this.

If you use the "Product Catalog" object, you can uncheck "visible" when selecting "Button" and the customer will no longer be able to access the shopping cart, see screenhot (1)

Instead, add a link to an order form or similar to the products under "Details", see screenshot (2)

If something else is meant, please explain in more detail.

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