Earlier quoted context omitted.
Why? Can’t you have a dormant or lightly used gumroad account integrated into your site/app. It’s not trivial, but could be worth it. Most frameworks have these services already integrated.
How would Gumroad prevent this? Hell Gumroad has an entire FAQ devoted to account suspensions so it's clearly an issue for them too.
Gumroad has their own failures, but if ANY issue with payment processing is intolerable, don’t bother running a business.