Perfectly good reason to purchase..
I have all of my music ripped to iTunes on my iMac. I like to listen to my music and watch concert DVDs on my high end TV and stereo from my patio. The apple remote for my iPod connected to my stereo, I find pretty useless. By spending $129 on the Apple TV (Australia), I get to listen to ALL of my music (not just what I can fit on the iPod), plus rip my concert DVDs and have them play on my TV - and all controlled by my iPhone using the remote software.
And before anyone chimes in about the 'real' cost of all this, the iPhone is work supplied, and the iMac is 4 years old. So it really is a small investment to make my leisure time more pleasurable. I don't really care about the renting/buying/downloading of movies/tv shows/music as I already have most of the media content I want already in my possession.
If I want to buy a TV show I just wait and purchase the boxed set from wherever in the world it is cheapest and rip it, then I've always got the original media as backup ie I can purchase the limited edition 4 season box set of 'The IT Crowd' from Amazon Uk for $47Aus. The downloaded version through iTunes will set me back more than that just for the first 3 seasons.
BTW got shipping confirmation for my ATV yesterday, contrary to some reports about delays.