Umm - Apple isn't *doing* anything along these lines, they simply patented the technology. A lot of people react to such patents as signs of impending doom, but they can simply be a side effect of a company encouraging its employees (often with cash rewards) to apply for patents.
Nor is the PTO in the business of deciding whether particular patents are ethically desirable or not; just whether they're innovative and non-obvious and in a patentable domain.
Not that this particular technology is particularly evil - the notion of having technology built into a device that keeps others from using it is hardly new and has often been thought of as a good idea (typically in the context of weapons that work only for the owner).
This can only be judged as good or evil in the context of how (and whether) they choose to use it. I wouldn't call this "spyware" unless they deployed it in a way that reported information to another party (Apple, the police, etc.) or acted against the owner's interests.
The practical issues with actually using this technology in a product make it very unlikely that they would configure it to act in a draconian way (like wiping and disabling the device automatically) - more likely is that whey would have it trigger a request for a password or special code.