Anthropomorphizing makes for poor analogies, but it's kinda the same way your acquisition of background knowledge of the Tang dynasty from whatever source material you used is not considered stealing or pirating either.

Theft involves removing from the source, Copyright violation is distributing copies without a legal right to do so. Training is fair use.

The judge found that it constituted copyright violation. Purchasing the books would cover their responsibilities with regards to training. The claim that they are destroying books to hold copyright is incorrect. The judge cited precedent that said instances of not destroying the originals were also fair use, his claim about destruction was to say even if this precedent were not considered fair use, the destruction that was already occurring (because it is easier to scan loose pages), invalidated one of the arguments against it.

The ruling was on training took the form

If A is ok then B is ok, but even if A were not ok, B might still be ok.