Users won't be able to use the product for what it's intended value is (better feedback and communication) if they're turned away so early.
Better put, a custom domain isn't part of the value we add, it's just a gateway to realize the value. Should we be charging for something that's not really tied to the value we provide?
Ex. A user wants to try it out but paying for a custom domain scares them. They stick to a free subdomain, but never really promote it since it conflicts with their own branding.
Admittedly you're making a good point here that users _would_ get more value this way through increased branding.
Better put, a custom domain isn't part of the value we add, it's just a gateway to realize the value. Should we be charging for something that's not really tied to the value we provide?