I have never had them charge me for anything like that. I get anywhere from 3-4 new phones a year and they do it for me every time. If they give you a hard time tell them "That's ridicules and you will take your business elswhere". Trust me they will do it.
Like Gary said, see if you can plug your sub into the back of your receiver. My receiver has two outlets on the back. One for constant power to a device and the 2nd outlet (this is where my sub is plugged in) turns whatever is plugged into it on when the receiver is on and off when the receiver...