"Hacking" is certainly not necessarily illegal activity: hacking includes all sorts of exploration, investigation, and occasional innovation using technology of all sorts. We have a microcomputer industry, a computer gaming industry, and easy-to-use PC interfaces largely because of hackers who were interested in creating and destroying. That is the sort of person you'll find at these dastardly "hacker conventions." Painting them all with such a broad brush is as wrong-headed as those who oppose gun shows because guns can be used to commit crimes.