I do share your concerns!
Making original content should be a clearly given criteria for posting on any Steem-app. The problem with dmania in particular is that the whole idea of a meme community is making and reposting memes.
While there is stolen content on Steemit as well, Steemit is a bank of knowledge which on a daily basis educates its users about what's okay and what's not okay. Dmania is basically just pictures.
But then again, maybe I shouldn't complain and start making memes instead;)