I think this comes from what kind of sports you are around when growing up. Football and basketball are two sports that are the most common and where being played the most during high school. I even played them myself in a team for a few years. And went regularly to the stadium with my dad and uncle to watch our home team play. So in university whenever my country was playing in a big tournament everybody would bet on the matches. I kind of grew into sports betting and never really considered to bet on sports that I have no clue about. For me sports betting is a way to try and make better predictions than the majority. If I have no clue about the sport I have to rely on the odds from the bookmakers. But when I am familiar with the sport I can try and take advantage of cheap bets.