Cross Country, as a Division 1 sport, is pretty cheap-- small staffs, relatively low coach salaries, small rosters, low equipment/facilities costs, and small staffs.
It doesn't generate much revenue, but the BYU runners that competed in Olympics generated a lot of recognition and positive press for BYU at the Trials, at the Games, and since then. Moreover, they represent the university at the highest levels of competition more regularly than basketball or football. Is that a good return? I think so, but I can understand how others might define "positive return" in other ways.