I don't know how much truth there is to this, but I've heard a story about the difference in French/Germanic word usage may stem from inequalities from the Norman invasion - the masters were speaking French, and the common folk were doing the dirty work speaking old English derived from germanic languages. So, the masters were dealing with the finished product with French words - beef, pork, mutton, veal, venison, poultry - and the commoners were dealing with animals with Germanic words - cow, pig, sheep, deer, chicken, etc