You're right, I don't know you. But my statement, while phrased in the 2nd person tense, does not require any knowledge of you, and does not in any way need to be specific to you. It applies to everybody. If you want me to rephrase slightly, try this:
Claiming a warranty replacement for damage that was a result of modding the phone is immoral and fraud; and the very reason why these devices get locked down in the first place.
The personal details of your life are not relevant to the discussion, and add no value to it.
People often like to frame things in terms of "evil" faceless corporations that don't get hurt if you rip them off. Of you getting payback for so-called "wrongs" they have done to you. But in reality, the expense of fraudulent warranty claims doesn't get absorbed by AT&T, it trickles down to all of us, the customers. And in more ways than one. Not only would such behavior pass on additional monetary expenses to other honest paying customers, but also is the very reason why manufacturers and carriers are locking down bootloaders, and otherwise locking down the phones against modification (write protected partitions, etc.). If not for fruadulant warranty claims (do to botched phone modding), the manufacturers and carriers would let us mod to our hearts delight. Locked bootloaders and other obstacles would not exist, because why would they care? Its not the "evil empire" you are hurting, its all of us.
If you decide to mod the phone, you accept the risk of bricking it, and having to replace the phone on your own dime. Its that simple.