FAQ #306: Does "Crediting" let me use whatever I want? FAQ #8: What are violations of the deviantART copyright policy? FAQ #572: What does deviantART consider "Fan Art" to be? Please read these faqs. In what way am I harassing? It's a simple warning of this site's rules. Crediting alone does not work here. You have to have FULL permission to use things that you did not create yourself. Nintendo doesn't allow people to use their official stuff at all. Most line art I find here is free to use as long as it's linked back to the original owner.
And sometimes people don't know that they're breaking the rules, it's up to the community to tell them. Sometimes people appreciate someone else telling them rather than being banned by DA and not being told they were doing something wrong in the first place.
And please educate yourself of the rules of this site. You're making a fool out of yourself.