Most of these types of sports are used to meet Title IX requirements.
I will take the Big Ten for example, just because I am more familiar with that group of schools including attending one. The Big Ten is pretty horrendous in baseball, the majority of the baseball players are receiving very little in the way of scholarship money. You may have 45 players on the team and 15 full scholarships available that is divided by 35 of the players and there are 10 walk ons. You look at women's volleyball, the Big Ten is arguably the strongest conference. Teams in the finals 16 of the last 20 years, 11 champions, 2 years with 2 teams in the finals, 28 teams in the final four involving 7 schools. So why is this? Great coaching? Great players? Volleyball is important in the midwest high school sports? No, Big Ten schools need to cover Title IX scholarship requirements, so in order to do this all 15 women on the volleyball team are on full ride scholarships. So in general, they are able to get better talent, which then competes with the better talent throughout the season.
So many schools are funding these off shoot sports to cover Title IX.
With that said, you also see some of these sports that are club sports, which are funded from donations, the players, ect. that operate and even play in leagues just as any normal school sport.