As for Steemit, inc. they are only obliged to remove copyrighted material if they are asked to.

But it is important for the community to help root out plagiators, I just do not know how to take the Steem-dollars away from people... how should it be done, and who should do it? It could impair the decentralization of the place. Honestly I see no other solution than a vigilant community... work, work, work in steemabuse-classic.