Val,
I'm with you.  I can't see any reason other than a mother's personal
comfort for wearing a bra, especially at night.  I encourage mothers to
air the nipples as much as possible.  If a mother complains about
leaking at night, she can sleep on a towel or two to absorb the milk so
she doesn't have to change wet sheets.  This bra thing drives me nuts!
In some of our hospitals, the doctors making their rounds check to make
sure the mothers are wearing "well-supporting" bras to (get this)
prevent engorgement...  Since bras have only been around this century,
isn't it just amazing how mothers managed to bf...

Susan Nachman-Srebrnik
Ranana, Israel