Priests, Ministers and Rabbis all favour black as the main colour of their ritual garb. Scientifically speaking, colour is energy. The colours you see are the ones, which are reflected, and not the ones absorbed. Therefore, what appears to be white, which is the culmination of all colours in the light spectrum, is actually reflecting all colours and absorbing none. What appears to be black, is absorbing all colours and reflecting none.
Witches can be either men or women.
Men and Women alike are called Witches. People are generally drawn to Wicca for several reasons. Many women feel left out of more mainstream religions because of the lack of feminine divinity. For them, the Wiccan concept of the Goddess as Mother of all Living fills an empty space in their spiritual search. Wicca much more accommodating as we do not see anything unnatural about psychic ability or the use of magic to create needed changes in one's life.