Why is "Men to the left! Women to the right!" significant in the book Night

In the book Night there is a time
when everyone arrives at the camps and are set up to be assorted.  The first thing that
the Nazi party did was to split families apart and to make the men appear small and take
their control away.  The women were sent to the left to either be sent away to another
cap, or they were sent to the gas chambers with their
young.

The men were often used for hard labor and  general
labor.  They would send them in a different direction.  In Elie's case, he and his
father were sent to the left meaning they would be in a labor camp.  His mother and
sister were sent to the right and on to their deaths.