Here's what the ammo companies know. First, inside of about 35 yards, most any load will effectively kill ducks, and 35 yards is about the range that most people should be shooting anyway. They also know that the average guy is generally way over choked to be really effective at that range. By making loads that are "difficult to hold together", they actually help the average guy in his quest to kill more ducks. That's the ballistics part, but keep it in mind.
The economics part is just about as simple. Most people choose their loads by price. And that means TWO things. The bulk of the people will reach for whatever is cheapest. In Winchester's case, this means the Xperts. But there is another faction that will try and buy success. They figure that if it costs more, it must be better. So, they wrap those loads in some sexy packaging, make some outlandish claims and launch an ad campaign telling everyone things that simply aren't true and can't be quantified and put a premium price on them. For Winchester, that means BlindSide.
Finally, they realize that there is a group of dedicated, knowledgeable waterfowlers that understand shotshell ballistics and have the skill to make clean kills well beyond those initial 35 yards when the situation calls for it. Here, the manufacturers provide very round, uniform steel shot with good wads in a waterproof package launched at a modest, but not excessive, velocity. For Winchester, this means Dryloks.
That about covers it.
I feel slightly sorry for a man who has never patterned his gun, who has no idea how far his chosen load will retain killing penetration. But I'm extremely sorry for the ducks he shoots at beyond the killing range of his gun and load - Bob Brister