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.

There is both a qualitative and quantitative difference between covering/remixing the art of others, vs. just putting the original up for ~~sale~~ free.