Recommendations like that at the post-grad level is so incredibly lazy. And dangerous, in that they're declaring that any source Wikipedia links to is to be considered "tainted", for some godforsaken reason.
Yes, Wikipedia is a paper-thin resource. All tertiary sources are. It's useful when you're dealing with people who don't understand what a basic concept is, or the like. You wouldn't cite any encyclopedia in post-grad work, unless what you were researching was encyclopedia methodology and systems.
Not using tertiary sources and instead relying on secondary and, in grad level research and beyond increasingly, primary sources is what post-secondary level research focuses on. Using encyclopedias like wikipedia stops being acceptable in high school.
This has nothing to do with the quality of the source itself, it has to do with it being tertiary in nature, reporting their account of someone else's account of primary research.
Just one of many academic sources on this; http://www.lib.vt.edu/help/research/...-tertiary.html