I'm definitely not going to try this because it sounds like an easy way to get in trouble, but would this work on a host like DO/linode/vultr, etc? Again, this seems really easy to detect
I've used Labrea on unused address space to make ARIN/RIPE happy back in the day and that was harmless, as entire /16's and /17's were unused. They used to nag about nothing in the /16's being pingable, so Labrea made it all 100% pingable
The agreement you make to get an allocation requires a certain level of utilization depending on the size of the block to prevent squatting and exhaustion of resources. This is a good thing, and if it was actually respected we wouldn't be in a mad rush to migrate to IPv6.
it only took 20 years to standardize after all. we're seriously rushing here!