It is on TV, but not nearly as much as basketball, football, or baseball and for good reason. Fan bases are built on the younger generations and kids today can pick up a ball or a bat and a mitt and go out and play three of the four major professional sports in this country.
Hockey on the other hand requires every kid to have his own skates and stick along with some ice to play on. I grew up in Illinois and I think there was one pond near my house that froze over for maybe one day a year. So for a good nine months of the year, I could play baseball, football, basketball, or even soccer whenever and almost wherever I wanted. If I ever wanted to play hockey, I would have to get someone to drive me to the ice rink 10 miles away. This tells me hockey does not really have a promising future in terms of its fanbase in this country and many others.