Print on demand dvdr so they are basically charging you for a crap quality release that is like a bootleg except it is legit, lol.
They might be from original studio master tapes but i doubt any remastering or clean up work has been done, or audio commentary tracks.
I always found Rockos Modern Life to have piss poor quality animation just like Ren amd Stimpy.
It has turned out that all nicktoons have to look this way even Spongebob.
Hey arnold was extremely annoying but he seemed to be the first character with the lemon shaped head or football head, until stewie griffin on family guy.