Why does AOL get to display their CDs at my US Post Office?
Have they taken over that much?

It’s advertising. AOL pays for the space.
Yes, thank you, I’ve been wanting to see/start a thread on this.
OK, so AOL pays for it. Well and good. Can I pay to have the P.O. put my cds and cards on their counter?
Doesn’t hurt to ask. Of course, I would guess it might cost quite a bit if you are competing w/AOL. But I have been wrong before!