At some schools the athletics program gets considerable tuition revenue as well (in the form of a tacked-on "athletics fee"). UF seems to have one of the lower fees ($57/yr), though when multiplied by 50,000 students, that still works out to a bit under $3m/yr. It appears (see sibling comment) that athletics contributes back some surplus to academics, though, so may be a net positive at UF. Not true at all schools, some of which have much higher than $57/yr charges (e.g. UVA's $650).