you are correct. But unlike film, music and music videos purchased from iTunes do not have DRM 'protection'.
iTunes distributes film of lesser quality than DVD, which itself is already compressed from the master tape. DRM is plain nonsense conceived to limit us further. The quality is in fact less than what is available through 'pirate' websites. and the same in regards to LoveFilm. Low quality, high prices, the joke is on us.
They love the control as much as they love the money
google will provide you with more information