What you say is true. Other than the Olympics, swimming is not a glamour sport. We had our parents and our girlfriends in the stands. Some of the time. Since our meets were in the afternoons, right after school, our parents didn't take off work unless it was a big meet.
Still, there must be something about the type of kid who will get up to be in the pool at 6 AM for before school practice, and will log another couple of hours after school every day... back and forth for miles over the same 25 yard stretch.
I think nearly everyone on our team was an honor roll student.
Swimmers and wrestlers are top on my list of college hires.