Do Catholics' offerings (tithes) support these colleges?>>
No. Most of these colleges are run by independent (which doesn't exonerate the bishops) religious orders who charge tuition, a lot of tuition. I wonder if parents spending so much money for tuition to catholic schools know that in many times and on many campuses, tenets of the Catholic faith are NOT upheld or held dearly by the administration.
I know some students from Loyola. In their marketing classes they study how to include homosexuals in advertising.