Myself, I'm quite open to new forms of entertainment, as well as those previously unknown to me. Even within my favorite genres, I'm more than happy to explore - but I'm still gonna rewatch at least one Star Trek show each year.
It doesn't matter that I've seen most of those show 6-10 times each over the course of my life; it doesn't matter that I've watched some specific episodes 20+ times already. What matters to me is, each time I see those characters and those locations, it feels like coming home.
(And more so than actually coming home.)
People anchor to different things like this, not just TV shows. Sometimes it's a real place (or an event in that place - e.g. vacation), sometimes it's a club, sometimes it's a video game or an outdoor hobby.
I know people who rewatch the same TV series every year and go to the same vacation every year.
Fear of change is deep.