I think there is some confusion being added to this discussion by all the talk of Comcast. Wideopenwest (WOW) is a competing cable company to Comcast. Unfortunately, in my dealings with WOW, I have learned that they do NOT make the Broadcast HD channels available to their subscribers as part of their basic package. They actually scramble those signals on their system so that you need one of their decoder boxes to pick them up. (I have an HDTV with ATSC/QAM tuner, and am unable to pick up these signals on the WOW system.)
I have been through several discussions with WOW, and they contend that they do not need to make these channels available as part of their basic package, because they already offer a Standard Definition version of these programs to basic subscribers.
I've been through many discussions with them, but that's the way it is. Even though Comcast offers this to Basic subscribers, WOW does not. So I use an antenna to get my HD programming. (This is a real pain in the Chicago area, with CBS broadcasting on channel 3 which is almost always blocked out by interference.)