I have a theory about this sort of thing.
The Golf Channel has a very niche audience. It gets a certain amount of its revenue from subscriber fees and the rest from advertising. They'll get the subscriber fees regardless. They can demand more from the cable companies if they want to increase revenue, but they run the risk of getting dropped or have people not subscribe to the packages that include Golf if they do.
So if they want to increase revenue, they need to put on programming that will get an audience so they can sell ads at a decent rate. That's probably fairly easy to do during the meat of the PGA season. At times like this, it's pretty difficult. With very little golf going on, they figure they can just punt the format and go for eyeballs by running whatever movie they can get their hands on. I'm sure if they could buy the rights to a college football bowl game and see a profit, they would do it. Breaking format when the golf season is essentially on hiatus is not that big a deal to me. It would only be a problem if this was happening during the golf season.
The Weather Channel does not have an excuse for what they're doing. It's just about getting eyeballs any time they can. Breaking format for them is inexcuseable since weather is something that's "in season" 365 days a year.