It's still a copyright violation; the DMCA, as mentioned above, is (iirc) more related to sharing of copyrighted materials on websites that host user-generated content (such as copyrighted videos on youtube or copyrighted visuals or code on github). The DMCA doesn't apply or need to be mentioned here, as the pre-DMCA copyright laws already cover this.
The copyright violation is coming from a server hosted in the US, so it's subject to US laws.
It would be the same if I took a DVD from the US that doesn't have a copyright in another country, went to that country to copy it, and then tried to sell it back in the US. It doesn't matter where I'm making the copy, it matters where I'm distributing it.
They probably rip off designs in the hope that they won't get found out. As soon as it looks like a hassle they will hopefully just move to ripping off someone else.
