Solve it the same way that they solve naming conflicts in programming languages: namespaces (Edit: as others have suggested).

There is both a "whitehouse.com" (it has a landing page at the moment, SFW) and a "whitehouse.gov"

I tend to side with Twitter here. Don't like it? Go create your own website (set up a laconi.ca node). I don't think that there is any inherent justification in the first-come-first-serve method of provisioning, maybe it is just an artifact of our culture?