I don’t have the sources handy, but IIRC also the following:
-For safety reasons.
-For tznius.
-In specific business cases (the example given was where a contractor demanded more money than was initially agreed to [not for a legit reason, he simply wanted to take advantage of the situation], and refused to complete his job until the person agreed to pay it. in this case the person isn’t obligated to pay the higher rate. this case was in one of the “halocha pamphlets” distributed in shuls.)