Yes be super careful with Labrea on VPS providers and dedicated server providers. They tend to get upset if you are trying to pick up IP's. In most cases it won't even work on KVM hosts.
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
Whether you own them or not is subject to a lot of debate and not clear cut. If you owned them, why would you need to fool ARIN into believing they are being utilised?
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.
> IPv6 is intended to replace IPv4. In December 1998, IPv6 became a Draft Standard for the IETF, who subsequently ratified it as an Internet Standard on 14 July 2017
it only took 20 years to standardize after all. we're seriously rushing here!
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