Interesting post, and glad it was resolved amicably! There's lots of things you could do, but one idea is to have an approach where your service states it will

Interesting post, and glad it was resolved amicably! There's lots of things you could do, but one idea is to have an approach where your service states it will use cached images for pages requested above a threshold in a particular timeframe - that would deter this kind of abuse, with minimal impact on genuine users.