The point is that it doesn't matter what you call the contract. You're thinking "oh that's just a sign" (ie ToS). Your error is that not all signs are equal. The 8 million dollars is the military base in this analogy. Being prosecuted for violating this ToS under these conditions is not interchangeable with others.

Fraud is just any time you intentionally deceive someone for material gain. Even without the ToS this would presumably still qualify as fraud. The ToS just makes it more straightforward to argue (IIUC, IANAL, etc).

A decent rule of thumb is that if your hack or neat trick results in money in your bank account that the other party wouldn't have paid out to you had they been aware of what was happening then you are almost certainly committing a felony of some sort.