There's a difference between copyright and trademark, and a lot of this sort of stuff can be OK under copyright law, but in breack of a trademark. It's become more complicated as extra bits have been added, such as "Registered Designs", but that's the basic element. You gallery image has copyright. People can't take it and put it elsewhere without your permission. But unless you'd gone through some extra procedures, they could say "That's a cool look, I'll copy it for Vicky", and stay legal. Depending on the source pf the stuff listed, trademarks could be involved. If they are, and the trademark holder discovers what DAZ is doing, they have to send a cease-&-desist letter. Trademarks are like that. Trademarks can also lapse. There's a regular renewal required, unlike copyright. And the original boat in the movie "The African Queen" might be commonplace enough that it couldn't be trademarked. As for the recently withdrawn models, a Blackhawk helicopter, an M1 tank, and a Hummvee, the Blackhawk has been restored. But what I have seen for myself, and comments in DAZ forums, suggest that the modeller made a poor job of the UV maps and texturing, and that was obvious enough that I am astonished DAZ didn't notice.