I didn't understand it either, until BattleBots got rebooted and I got really into it. I was catching the episodes live, talking with people online as the episodes aired, talking about ideas and strategies, etc. Now I understand.
It's just to be part of something. To be part of a story. Same reason people do anything.
Until someone has solved the philosophical problem of meaning, all we really have is storytelling, and the stories that happen in sports events can be easily understood.
I feel like this can be applied to anything. People enjoy what they enjoy. Lots of things I don't understand like reality TV. My girlfriend loves Big Brother. I don't get it. But I don't need to. She just needs to enjoy herself like I do with things I enjoy.
Pick whichever team is most likely to win and feel great. When they inevitably regress to the mean and start losing games, pick another winning team. Rinse and repeat for great success!
No one thinks they have an impact on the game while watching from home..? People follow sports for a lot of reasons, some sillier than others, but I'll just list some of them:
Gives a sense of community. If you've ever lived in a college town there's something really cool about everything in the city stopping in it's tracks because everyone has this common interest.
Gives some nostalgia. If you grew up going to games with your family or friends it reminds you of that time.
Just to have some stuff to talk about 🤷 you know everyone at work is going to be talking about whichever sport is popular near you so it's nice to be able to talk about it too.
To watch an impressive show of athleticism similar to the Olympics.
To play fantasy. I'm not really into it, but a ton of people love the competition of fantasy sports.
Because they bet on the games. It definitely ups the stakes when there's money on the game.
And a sad reason that's somewhat common is that some people who don't have anything good going on in their life like to latch on to a successful team to feel more successful themselves.
Most people who watch sports or follow a specific team recognize that it's a little silly, but who cares because it's fun and a whole lot of people are doing it with you.
I feel like I should chime in. Ball sports mean squat to me, but to each their own ya know..
I like watching wheel sports though, and I don't mean car racing. I like watching BMX flatland sports, as every rider has their own unique style and those different styles inspire my own flatland style.
TL;DR - There's more to sports than just dudes playing with balls.