Do the groom and groomsmen have to match??

My wedding colors are pink and grey. My bridesmaids are wearing a soft pink called petal and my MOH is wearing darker shade of pink called quartz from Davids Bridal. I am wearing white and my fiance is wearing a black and white jacket, black pants, and bow tie. My question is what color suits should the groomsmen wear; grey or black? I want grey seeing that that it is apart of my wedding colors but with my fiance wearing black and white I'm not sure how it would look so black would be playing it safe. Also we are going to have the best man tie and vest in quartz to match my MOH and the rest of the groomsmen in petal to match with the bridesmaids.