Why not Labor's Day?

Question:

Recently I was asked why we say " Mother's Day" but " Labor Day" (not "Labor's Day"). Why not " Laborers' day"? After all, we labor so hard, we are actually "laborers".
We have also "Father's Day" but " Christmas Day" (not Christmas's day).

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( English teacher )

"Mother" and "father' are people and the days chosen to honor them are called their days. So the possessive forms of "mother and "father" respectively are used to name their days, i.e.. "Mother's Day" and Father's Day".

"Labor Day" is a day that has been chosen to honor all working people. "Labor" refers to the work done as well as the workers collectively. we don't normally use an apostrophe 's' after the word "labor" to indicate possession. Thus "Labor Day" is used.

"Laborer's Day" does not sound so neat.

As for " Christmas", the word means " the mass or festival of Christ". "Christmas" is not a person, so we can't put an apostrophe 's' after it. "Christmas Day' means "the day of the festival of Christ".

I was looking for some information about the holiday we are celebrating today here in Brazil, and I found this interesting fact. I asked something about Labor's Day and Google corrected me. I confess that, even though, I was in doubt. Up to the moment I found this interesting address, where we can solve a lot of other question. Take a look and see if you don't agree with me!!

http://www.englishdaily626.com/qna.php?015

This is my contribution for the day! Have a nice holiday!!!!!