It absolutely would - if you accidentally pressed back or refreshed the page, if fields don't pass validation, if there's a server error or a network issue when

It absolutely would - if you accidentally pressed back or refreshed the page, if fields don't pass validation, if there's a server error or a network issue when you try to submit, if your credentials expire while you're editing, etc. Not defending meetup but people have every reason to try to override default UA behavior.