I never followed sports (though my dad spent his career as a coach and university athletic director and brought athletes by the house all the time - Olympic gold medalists, national and world champs, people who went pro, one who has drafted by the NHL and the Majors, he never was much of a spectator and neither am I).
I haven't had broadcast TV since 1988 except for having a roommate for a year who had a TV in his room and used to get me to explain/translate Wayne's World for him (and really didn't have a TV regularly since 1981). Have never had cable TV in my life.
Nevertheless... I used to know all the celebrities simply by running the supermarket tabloid gauntlet every time I bought groceries. More and more, the supermarket has junk food and drink, so I now feel completely out of touch with all celebrity culture.
People are always saying "You know that ad" and I cut them off there. Some protest that I don't even know which add they're talking about and I have to explain that if it ran on TV, I didn't see it.
And sometimes, people have to explain why something is funny. "It's a parody of that ad. You don't remember it?" If it ran after "Mama Mia, I can't believe I ate the whole thing!" then no, I don't "remember" it.