You called property "weird" so I wonder whether you are aware that property is weird exactly because of the double spending problem. A land title registry gives you double spend protection, not just irrevocable publication. Your point of course stands, since you're trusting someone with enforcement, you might as well trust them with double spend protection. I'd say decentralized irrevocable publication (e.g. certificate transparency) is much cheaper than decentralized double spend protection.