Price business pipes where they won’t cut you off for saturating that 24/7.
[edit] and that have good deliverability worldwide, no weird paths to other consumer IPs that intermittently fail to route or inexplicably have dial-up transfer speeds. And have anything like a real SLA.
I don't think they legally can in number of European jurisdictions. This isn't like Comcast overselling their copper cables - brand new fiber paid for by the EU comes with certain obligations.
It's a bit surprising that you were not getting significantly better prices than individuals.