This amounts to copyright violation. CelebrityNetWorth went to great extent to organize this data and holds copyright on their site. Google is duplicating and redistributing this research without permission of the author.
What's worse is that Google essentially uses its monopoly (or at least extreme popularity) on search to essentially extort people into going along with stuff like this. If the site in question actually filed a DMCA notice or requested a takedown in a more tactful manner (assuming he could actually find someone to talk to about it) Google would probably just tell them to update their robots.txt file so that the site doesn't show up on the search result pages.