For years, I didn't like Cheers, because I couldn't see a single character on the show that I respected (with the dubious exception of Frasier). Now I realize that was the point of the show. Same with Seinfeld -- you don't laugh with the characters, you laugh at them.
There are times when Patricia Heaton's character on Everybody Loves Raymond comes off as a world-class B----, but that's what she's supposed to be. The show wouldn't be as funny if there weren't moments when Raymond states his mind, gets a dirty look from his wife, and slowly says, "What I meant to say was . . . . "