how exactly is he "abusing" the coin?
there is "use" and "abuse", please clearly define what you are saying. And of course lets not forget your reasoning that access to a botnet//server farm//as-many-computers-as-i-can == ILLEGAL BOTNET.
This is not an ethics discussion, it's mostly for those with a passion for CPU mining, GPU discussion is allowed since they are treated the same nowadays.
Botnet operator - spreads his malware and gets coins for free. Dumps them for whatever the price is. Regular miners compete with someone with free electricity and hardware.
GPU/ASIC mining - spends money for hardware and electricity. Miners compete with one another by investing, and they sell at good prices. They also stop mining at low prices reducing difficulty.