I remember when satellite radio came out, I thought it was going to be so revolutionary. Then the iPod revolution made it pretty much irrelevant. Yet they seem to think they can follow a cell phone business model, charging extra for random services that should be free. If I were a subscriber and was told I could pay extra for this "service," it seems like the sort of thing that would lead me to cancel my service in a pique. Boo, Sirius.
Now that I've written this, I actually went to the Sirius page, and realized the $3 fee isn't specifically for Sonos support, but for internet streaming in general; Sirius charges subscribers to listen online, through Sonos or through their own computer. Which seems even worse, in my opinion. Of course, that means their existing subscribers don't seem to mind, but considering Sirius is basically arguing that, without their proposed merger with XM, they cannot continue as a going concern, maybe they should wonder if incidental fees like this are scaring people away from the concept of satellite radio.