Different Target Audience
I've mentioned before how on HGTV, they avoid talking about the relationships of two people of the same sex who aren't family but live together. Well, it's not much, but on an episode of CA$H CAB, they showed two ladies kissing on the mouth twice. (The episode synopsis is not helpful.)
By the way, I have no idea why DEADLIEST CATCH is supposedly "the most popular nonfiction show on cable." I already think no one's going to recognize the references to shows I actually do watch in my projects.