What is unethical about segmenting customers based on the devices they use? Would it be better to do away with all forms of "unlimited" plans and just charge per MB?
Unlimited plans have already been done away with by everyone except Sprint. What's at issue here is them charging extra for data bought by the byte.
I believe that you should be able to purchase data and share it amongst as many devices as you want (a small activation fee per cellular device may be acceptable, but nothing of the sort should exist for tethering, since there is no perceptible difference for the carriers) . This is how it works for wired internet, and I don't see why wireless should be any different (with the exception of any wireless specific network management, but that's not at issue here).
