The party poker ceo must have a big smirk on his face. They stopped transacting with US players when that law went into effect a few years ago.
It's called in rem jurisdiction. Welcome to the US legal system. A judge likely signed off on a court order that the domain names themselves - physical objects - are violating certain laws and therefore can be seized regardless of a successful conviction of the personal defendants in the case.
How can you argue this is a bad thing? Shut the damn thing's down, the people behind that shit are scumbags