Hi,
Thanks for the additional information @PolishedGeek and thank you for the counter argument @progreccor.
It's true that the server logs the IP address for every page request anyways.
However, it's done in the server access logs that a hacker wouldn't normally have access to even if he was able to have a backend / database access (of course, everything is possible if the website / server is not configured properly or if the hacker is able to elevate the user permissions etc).
All in all, it's a matter of how far you want to go.
Some pages online also mentioned the need to encrypt the user data... But I don't see how we could realistically encrypt the user data (email address, IP address, address of the user in an order, etc). That would be so impractical for an ecommerce website and so much overhead for something an attacker would still be able to circumvent.
So I'm not sure if it would be useful to add such an option for the cart user IP address or if other things should be done. The GDPR is for now a big mess as there is no clear cut on anything technical. Of course, they say that the user address should be securized (encrypted, anonymized) but, they don't talk about how impossible this would be for the address of the user in an order on an ecommerce website and what should be done in that case.