In the rare occasions where we do flip a coin, we have the winner select the color of ball AND the pallino, not one or the other. We don't want to wait around for people to make what are really inconsequential decisions. We want action!
The coin toss is mostly a waste of time anyway. You have to locate a coin (half the time no one has one handy), decide who's going to call it, then flip it. Then...when one team wins the toss you have to ask them to choose the color of ball or pallino or whatever way you work it.
The one who wins the toss looks to his teammates...
"What color do you want?"
"I don't know, what color do you want?"
Gimmee a break will ya? Let's get the game going.
Look, the color of ball has no bearing on play, unless you are superstitious. Besides, players often bring their own color balls anyway - not always the traditional red and green. So, the only real choice is who will roll the pallino first to start the game.
Wayne Farinacci gives his tourney participants a flipping coin that has a red bocce ball on one side and a green one on the other. So, you call "red" or "green" instead of "heads" or "tails". I would suggest that whoever wins the toss should take the color s/he called AND the pallino...e.g. you call "red" and it comes up red - you get the pallino and you roll red. You call "red" and it comes up "green". You get green and the other guy gets red AND the pallino.
If you don't do it this way you are back to where you were with the regular coin. You call red and win the toss. Are you going to let the winner of the toss take his choice of ball color OR pallino, then give another choice to the other team? If you do, you're back to square one in the coin-tossing game. You make the call!