Come on. Appending a URL to the copied text doesn't break anyone's experience. It's a very tiny inconvenience at best.
As for them pre-judging any copy and paste as inherently unfair, most people on the Internet copy and steal things without giving credit. Appending a URL to a chunk of copied text is a way of nudging them to cite the material. As for fair-use folks, I see it as helpful. I always cite material I copy from elsewhere manually, but now the script does it for me. In either case, it's a win.