Son did not join a frat and found his tribe at Case.He still sees his Case friends, a nice group of boys, some of whom found jobs in Cleveland, others in different cities. Freshman boys always live in the freshman houses. Some will move to fraternities second semester freshman year or sophomore year, but many will choose not to do that. This website says 70% of Case undergrads do not choose fraternities or sororities. With that, quite a few fraternities are
very service oriented, and not entirely focused on social life, although thats still part of their purpose. . There are off campus parties by upper class years, as well, and some non Greek boys will date sorority girls and have some social experiences with sororities. Its not firmly delineated, Greek or not Greek and plenty of athletes at Case are not Greek.
Also some fraternities do not own houses, so those students will live in any housing and may still be part of some social and service events at their fraternity. I also know sorority members who choose to live off campus and not in these sorority house.
https://students.case.edu/campus/greek/recruitment/factsheet.html