This is not - I repeat - not in defense of the banner and/or logo meisters:
I believe the (original) reason the stations post the overlays is so recordings of shows can not be re-broadcast, or perhaps, re-sold without the viewer knowing the origination of the programming.
I will be happy to sign or otherwise support any movement to ban or limit said obnoxiousness.
Larry
www.fineelectricco.com