This is why I don't trust in Universities anymore. If the souce is properly cited, then use the source. You'd have to read the source, to know it was properly quoted. Never should you use Wikipedia as a credible source. That is insane
Wikipedia is just a very large compilation of cited essays. People cite it for the same reason they cite other people's essays. Because all the info is compiled into one place and they don't have to be citing 6 different things when it's all there and already cited on the other essay