Does anyone have an Apple TV and find it useful? Am I missing something?
I think as a movie rental device I agree with you: Apple charge too much (shocker).
But look beyond that, you can subscribe to Netflix if you don't like Apple's prices.
I got one on a bit of a punt. Yes the menus are a bit clunky - I expect better from Apple - but what it is most used for in our house is streaming YouTube from the iPad to the TV. That's what it's brilliant for. Sit in the comfort of your sofa and browse YouTube with the super convenience of their iPad app and enjoy watching it on the big screen.
Likewise our little one watches movies the same way. We have a collection of movies saved to the iPad which she is allowed watch. She can stream them to the TV without having to go near the Internet and much easier than loading DVDs and needing help with DVD set-up menus. So easy a child can do it.
Also good for showing family photos in the same manner. Streamed from an iPad or iPhone is much easier and more informal than trying to show them on a computer/laptop. Seeing them displayed on a TV removes any corporate powerpoint feel. Much more homely.