OK - on the off-chance that you are actually serious about your question, and yet have no capacity for internal thought or logic, a condition proven repeatedly.

a) The repeater *does* report back to the tower, just as your cell-phone. How do you think cell-calls are traced? This is not just 'movie' stuff, but everyday stuff. Not just cell phones, but your car, your FitBit and much more. The point of this device is that you are in a poor coverage area. Otherwise, you would not need it. Meaning, it acts as an amped-up link for your phone.

b) Therefore, the moment you moved this device onto another tower, your provider would know it. They live for jackasses, cretins, donkeys and assorted other detritus - such as you - who somehow feel that agreements made in good faith are to be ignored for their personal benefit. Let me put it another way - if you can figure out an angle to cheat, they have entire staffs dedicated to thwarting idiots like you.

You really do need to get a life - and/or invest in learning about critical thinking as you are, clearly, a tick on the soft underbelly of society in your present state.