You aren't missing anything and there was a thread on this very topic recently so you might want to search for it for more detailed info.
The short answer is that you can connect an iPod to any receiver using ANY of its analog inputs (CD, DVD, Tape, Aux, Video1/2/3, etc). Receivers that advertise 'iPod compatibility' simply provide additional features like scrolling the song name on the display, using the receiver's remote to control the iPod, etc.