I'm torn. On the one hand, scraping helps break down walled gardens. On the other, we're talking about personal details being used in novel ways that no LinkedIn user probably understands. I doubt any LinkedIn user writes their profile expecting HiQ to scrape it, assign a "flight risk" score and alert your bosses.
Users know their information is public and they have the option to make it private on Linkedin. If Linkedin is worried about the privacy of their users they should let them know about the risks of having a public profile.
Human beings are hardwired to do things that they see others doing unless there is a really clear connection between the actions and disaster. There has to be another mechanism to deal with probably small, but unquantifiable risks.