Plagiarism is one of the worst things in real world
You have serious problems if you think that plagiarism is one of the worst things around. What about rape? murder? fraud?
OP says one of the worst things. Plagiarism can give the tag of academic dishonesty and sometime copyright violations comes with hefty plenty.
Out of three you mentioned, I did not know if first 2 are committed online and plagiarism is equivalent to fraud only.