I use iTunes occasionally for first run movies. They are about the same price point as other on demand services and I buy through Apple TV and just rent them. It's handy and beats renting on the iPad because they stream immediately on Apple TV whereas they must be downloaded to the iPad when rented or purchased which is a substantial wait time between ordering and viewing.
Now as related to dated media? They are gouging. Movies readily available on Netflix and other providers are billed at about 80% of the price of a first run rental. It is ridiculous and while buyer beware sounds great I still see their attempt to gouge me as exactly that.,,,an attempt to gouge the unknowing or naive folks who pay these outrageously high fees for watching something TNT or AMC runs with regularity.
I suppose their is a market that pays for these. My guess is folks who don't have cable services for TV viewing....a market that is larger than many expect and it isn't a new market. Sure many folks are migrating away from cable now with the Hulus, Netflixes, and other streaming providers but there were, and still are, a great number of people who never bought into cable services yet embraced streaming as their exclusive means of home entertainment. The ones I know aren't lacking for money either, most frown upon the reality of TV news and entertainment shows as harmful to their children so they prefer entertainment ala carte where they control all content.
Still though I think iTunes should examine a subscription model for dated content because the prices they charge for this genre are out of line as I see it.