Why email isn't readonly on checkout?

Why the email field on checkout screen is editable? Shouldn’t it be readonly with signed in user’s email address? I map posted transaction in “App: Sales” sheet to certain rows in other sheets in which I use email address for matching. So if user changes email address at checkout, it is a problem with me.


Because not all apps have signed in users. I have a public app that has buy buttons and the user needs to put in his email address on the Stripe dialog. This is not a bug and I reclassified it.