I went to grad school, but most of my peers didn't. I don't have full knowledge of the lives of everybody I went to school with (no facebook then!), but a pretty standard path was "graduate, flail a bit before getting a shitty first job, get a somewhat better second job, get married and buy a house by 23-24." Also, tuition, room, and board came in just under 5 grand my first year. We'd gone beyond "pay for it with a summer job" by then, but not by all that much.