Residents of Ann Arbor, Mich., will be familiar with Hash Bash, the annual, smoke-filled rite of spring set for the first Saturday of the month. This year, after voters legalized recreational marijuana statewide in November, the event, which brings thousands to the campus of the University of Michigan, will have a decidedly celebratory atmosphere. But even with that political success, Hash Bash, which got its start in 1972, isn’t going to disappear anytime soon.

Part of the reason, as organizers have pointed out, is that there are still plenty of drug laws to protest. But the real reason Hash Bash will live on is less political than cultural.