You could just place some forum, blog or whatever on such a domain. Of course there wouldn't be much or no content at all. But how do you want to prevent this?

You could just place some forum, blog or whatever on such a domain. Of course there wouldn't be much or no content at all. But how do you want to prevent this? With a "there must be regular content updates" rule? No problem, just create some nonsense text with Markov chains or copy some wikipedia pages. Now you would have to add a "Content must make sense" rule. Much fun to enforce this.