Kiwifarms, now banned, official twitter page said their goal was “exploitation of the mentally handicapped for amusement purposes”. ( Source:
https://archive.is/jYp5p ).
I think Kiwifarms is (borderline) criminal. Null, the admin of the site, outright said he was ok with users posting stolen financial information, such as Social Security Numbers and Credit cards. Source: https://archive.is/0fOcS . There are many examples of private financial information being posted on the site.
I would describe them as operating with a paper thin layer of "plausible" deniability. Officially you aren't allowed to harass or interact with the targets. But posting their home address, stolen passwords, phone numbers, and information about relatives is all allowed.
But even the rule against interacting with "lolcows" (called "cowtipping") is haphazardly enforced. For example, one user had sex with a "lolcow" and posted photos. The admin explicitly said they would allow the content to remain up: https://archive.is/zYnpK#35%