One overlooked feature of this feature is the Sign in with Apple. You can use the App Clip to make a purchase and at the same time you give the vendor an anonym

One overlooked feature of this feature is the Sign in with Apple. You can use the App Clip to make a purchase and at the same time you give the vendor an anonymous email address which they can use to contact you with more information about their service. If you don't want any information, you can cancel that anonymous address. I don't see how this can be done in a web app.