Our school has this, but for most kids sport means intramural sport or something like yoga, fitness, conditioning etc. Intramural basketball may be pick up basketball if motivated but also just standing around with a ball for half hour and then being a cheer squad for whichever basketball team plays at home. The time commitment is not comparable, 2-3 days for an hour maybe, compared to kids playing 6-days a week, traveling to games etc. Conditioning can be a time suck if you are doing the real football/baseball/softball/lacrosse off-season workouts but for the non-athletes it is half hour of walking on the treadmill/outside if nice weather. There are also things like rock climbing, farming etc. You can easily go through the entire year of ‘sports’ without breaking a sweat.
My kid complains all the time how all his friends get to hang out on Saturday while he spends most of the day on the bus/playing games/trip back. There are very few freshmen on the teams in general in our league. It makes sense for varsity teams because the PGs take those spots every year but even JVs are loaded with juniors and even seniors in some sports. There are more freshmen on thirds but a lot of sports do not have them. So even kids who do want to play may get cut, or directed to sports like cross country that do not cut. I think the small schools need more kids to play to field all of the teams but at the big schools there are a lot of kids that do not care for sports at all, and set up their schedules accordingly. And after freshmen year they get out entirely for music, dance, theatre, science competitions or other other things they are pursuing. They may need to continue the yoga twice a week to check the box, but I think calling it playing sports is a stretch, and the time commitment is very small. It is some exercise at best.