Not only do they overlap; often they within themselves contain a variety of beverages which have nothing to do with each other and appeal to different distributors. Often one distributor would excel in about 25% of each of the three companies' offerings but has to follow all of the protocall and often buy one or the other from an ignorant distributor at a premium price to make out the whole selection. And in the midst of all of this various DPSU etc employees get their commissions/numbers etc when in fact they're in essence trying to sell quiche to McDonalds and discounting it heavily to get it in while blocking its available to others so that all of the French restaurants have to make a deal with McDonalds to get their quiche. How about selling the stuff to the people who know what it is and how to market it? Oops... radical concept!
Keep in mind that the King Of Pop\'s crown is not made from a bunch of melted aluminum cans!