Telecos make minimal amounts on the hardware - its all in the batshit insane service costs. To give an (out of date ) example, back when ATT was getting rid of contracts I talked with some people who knew the ins and outs. On the contract model, the first 6 months paid for the device subsidy and the network, the last 18 months was pure profit. They where all super excited about the financial gains of no longer needing to do phone subsidies, but still have the customer locked in for 2+ years.