The point is that as a line worker, you don't own the machine so you can't claim that this came out of your salary. Someone else bought the machine so that you can use it. Most likely, the owner of the machine has the money to buy it because the owner has showed they are efficient at allocating capital in the first place hence they are rich enough to buy such machines. The machine is capital and it increases your productive capacity. If it wasn't for the capitalist who bought this machine, who would decide what the right machine is to use? Would it be the government? It's not the government's place to decide what types of machines and other capital workers should be using in their factory or office. This is obvious because the government doesn't have the financial incentive to pick the best machine in the first place. This implies that governments' that take control of this type of capital have less dynamic economies. See Cuba, North Korea, or Venezuela. Does my line of reasoning make sense?