Submitted by Mark Kinsler
This May 3, 1939, Eagle-Gazette ad is interesting.
It would seem that Lancaster food store clerks were unionized in 1939, which seems remarkable now that unions for ordinary workers are long gone.
Apparently, store hours were dictated by the Retail Clerks Union, which would be why stores closed at noon Thursdays, thus ensuring workers 1.5 days off per week.
It must have been a formidable union in its day.