You owe it to your children to be your authentic self for them. A parent sharing their favorite sports teams (or other personal interests) with kids is giving them an opportunity, not a burden: they don't have to love your team or even share your interests, but they can if they want to. Then for the rest of their life, if they hear anything about your thing, they'll have that personal connection and associate it with you. I take my daughters to football games every year, and they care way more about the snacks and cheerleaders than the game, but they'll always remember it's something I loved and wanted to share with them.