The problem now, is that the paper has just figured out a cost effective way of obtaining digital art. Your story sets a precedence for further copyright infringement.
In essence, they try to get it for free (COST = $0) and if that fails on the threat of legal action, an offer for substantially less (COST = 30%) is made with little regard or fear of litigation. As this model is implimented more, the market value of legitimate work will be diminished, further hitting us in the back pocket.
This should be taken up with your government representative to encourage legislation, that if copyright infingrment is proven, as you did, a fine of $1000 per infringement applies. the government recoups the cash and re-imburses the plantif. Just a thought!