When they talk about well rounded students: They do value working on a farm. Or going to Guatemala and building wells for people. Or construction work building houses. It's definitely not just about doing ballet and fine arts.

I was the only kid in my class who didn't go to college, but I went to one of the top 3 prep schools in terms of Ivy League placement in the country, and the entire focus for extracurricular activities was doing volunteer work. Sports, music, fine art and theater were all there as a potential route, but the advisers pushed kids who wanted to do those things as a career away from leaning on them as a way to be "well-rounded" in the eyes of the college admission boards.

TL;DR In my experience, a kid who had no creative talent but took a summer to build houses in Ecuador was much more likely, in the 90s, to get into the Ivy League than one who played violin, or football.