Given the additional cost to the service provider, it's not that appealing to them. However, this has been done. There was a lawsuit about it, in fact: http://

Given the additional cost to the service provider, it's not that appealing to them. However, this has been done. There was a lawsuit about it, in fact: http://www.pcmag.com/article2/0,2817,2327137,00.asp http://www.pcmag.com/article2/0,2817,2327137,00.asp