I for one am not a big fan of those TOTALLY USELESS “parking” pages, with ad placements that are “misleading” to say the least. But we are still living in Capitalism after all, and there’s very little we can do.
More importantly, it’s technically difficult to define “proper use” of domain names. How about an “under construction” page? And how about an under construction page with ad placements? Are we going down the dangerous path of censoring content at the registrars’ level (like some “cowboy” registrars already doing)?
Industry outsiders may not know, but domain names could be used for backend purposes like mail, data and name servers as well. So who is to judge if a domain name is “properly used”?
The closest we could get is perhaps to incorporate a justification policy like that for IPs, but I doubt it’s even relevant when we’re heading to a brave new world of .whatever gTLDs, not to say domain names as we knew have already become less critical (essential) with Facebook and Twitter. Embrace for impact.