You're saying here that all of Mozart's work was created in the name of an Austrian emperor or whoever.
With this in mind, your works are subject to a contract, where the method of payment is agreed upon with the user. The work remains yours, but a licence is granted under certain conditions to the professional user, who may be an author. That's what they say.
Are illustrators' rights better defended in other countries? Is there a resale or a moral right to their works? I can't help but think about the comic strip Astérix. Even if it isn't as popular in the English-speaking world, I think everyone here knows that it was illustrated by Uderzo and written by Goscinny. Is the copyright on the illustrations clearer in other countries?