The biggest land owner in the world is not the Catholic Church............but McDonalds Canada.
So their major is selling burgers, one of their labels buys land/buildings. Another label manages agriculture "conglomerates" (basically aggregators of food (beef/potatoes/milk/wheat/orange jews/salads), like iTunes is for digital music).
You are producing "eco-friendly" beef and that gets you signed to the food label. You need buildings/land for that biz to expand, so the other label which specializes in it helps you with that. Since it all ends up running under the universal (no pun intended) major label, you are signed to that (indirectly) and if your biz turns out to be running good, your beef may end up being sold nationwide in their burgers.
Got the analogy? It's the benefit of combining forces (aggregation) and if done correctly, gives you a bigger market to sell your product to. Sure, the intermediary "labels" get their share, but you pay for a service and for people who specialize in the specific disciplines. So your specific product ("eco-friendly" beef) may have a local market of let's say 2 million a year and you end up with 300k in your pocket, but if all the labels play together (and your product is that good), you may end up with a 5 million in a 50 million dollar market.
