Criminals are bad, evil, jail etc etc. I agree. But while the core problem that creates this environment is not solved, nothing will fix it. Not even if you bomb the hell out of it. Ethics, morals and whatever people call only exists if economy is stable. If you let this sort of opportunistic environment exist there will be people to work in it
Dire economic conditions increase crime, that much seems true, but as long as it is profitable, there will be crime, under all economic conditions. It is, as you say, opportunism.