I actually think it's ironic for precisely that reason. Similar to covering music, there is a legal precedent for making books available in public libraries - though most cover artists don't pay the royalties, and in this case this online library is not paying the GP. In the case that GP did in fact pay the fee, I rescind my criticism.

I think GP's criticism is valid. The toplevel poster is creating work that leverages the creativity of others. Regardless of whether or not he's paid a fee to do so, it's still funny to see the indignation about sharing, when the person's current project involves using the work of others.