Wages absolutely have everything to do with it, why deny it and try to make it a political issue (lol)?
Few people do the job because it's an extremely bad deal. You will make more as a bartender than you will as a teacher, with the added bonus of a restaurant manager willing to kick out unruly guests whereas a school admin will likely side with the parents.
Typically the jobs that are most useful to society pay extremely bad (janitors, garbage collection, teachers, nursing assistants, dock workers, delivery people, etc). I'd checkout bullshit jobs manifesto if you haven't"