Oh ... this is actually simple to explain... its all got to do
with genetics... as you know, we all evolved from primates and as
such we still inherete our hairs in our body... did you know that
we have the same amount for hair as a gorilla but only our are
thinner... and also our ancestors came from multiple places on
earth Africa, Europe, etc... and so our genetic makeup differs...
this DNA strand called gentrio phlonomine dictitates the hair
growth on our bodies... the DNA tells that some may need to sweat
their armpit more so they have lesser hair and all the nutrients
has to got some where so its transfered to the legs...
Does that answer your question? 
