Typically they get paid the initial listing sum of the auction (at least) and what happens on secondary market is not their concern, similar to classic art pieces.

Royalties can be a thing provided NFTs are traded using a smart contract that pays royalties to the creator but it's not that common since artists are compensated well enough by the first approach and don't need to milk secondary market trades.

On stolen content no, but if you re-sell the NFT you bought from me, I get a royalty. That's part of the appeal for creators.