I think Deb may be right.  I started 25 years ago as an
     anthropology graduate student who took a job running a
     state historic site.  Moved through a soft money
     archeological position to a hard money state
     archeologist job, and then to the museum - I went from
     digging it up to taking care of it, all with the same
     employer.  There were no "museum studies" courses
     readily ("obviously"???) availble to me when I started,
     although I was always fascinated with museums, and
     worked in one at the U of Kansas while in school.  On
     the other hand, the folks who apply for jobs here now
     often come out of public history or museum studies
     backgrounds.  I suppose that some "old timers" must
     have gone directly and deliberately into museum work,
     but I don't recall the opportunity ever being real in
     my youth.