I am saying that Miner B has a pricing advantage due to the transit and can sell the same data for less allowing them to achieve much higher profitability at a price where Subnode c would actually be losing money. Miners don't really care that much about free versus non-free data. If they want to give away free data, they can just make it so you get that data slowly so the cost is minimal. Similar to how you can query the nasdaq servers for free pricing information but it is on a 15 minute delay so traders pay significant sums to get the same pricing information without delay. You have a point on specialization if there are data service specialists then it will be because they are peering with all the miners in a Bitcoin LINX like system.