1999 seems pretty late into the evolution of the web for a creator to be so concerned with scattered instances of their work being shared online. 1995-96 I'd believe--the web was mostly still new, norms hadn't adjusted to its presence. But by 1999, the web was well underway, and it would've been weird for random scans of comic strips not to be found freely in all corners of the internet. Did he really email hundreds of site owners?

(Unless the places he was sending his form letter to were hosting most of his back catalog, which would amount to full-scale piracy.)