Why do home teams wear white and visitors wear dark uniforms?
Home teams do not always wear white, in both hockey and football the home team wears dark uniforms primarily, although in hockey the home team has only worn their dark uniforms for a short time.
The distinction began in 1952 when the Canadian Broadcasting Corporation (CBC) began televising hockey games. The CBC found that when the two teams both wore dark or light it was impossible to tell them apart. Remember that not only was the clarity much less than it is today, but also it was also broadcast in black and white, so blue would look much the same as red. Many Montreal Canadien fans were aghast to find out that they were cheering for a Toronto Maple Leaf.
Making the home team wear the lighter color solved the problem; they of course choose the home team to wear the light color so that they would appear a little clearer than the visitors.