This is what Wikipedia actually says about citing journal articles:

    Where available, academic and peer-reviewed publications are usually
    the most reliable sources, such as in history, medicine, and
    science. But they are not the only reliable sources in such areas. You
    may also use material from reliable non-academic sources, particularly
    if it appears in respected mainstream publications. Other reliable
    sources include university-level textbooks, books published by
    respected publishing houses, magazines, journals, and mainstream
    newspapers. You may also use electronic media, subject to the same
    criteria. See details in Wikipedia:Identifying reliable sources and
    Wikipedia:Search engine test.

Their policy appears to be the opposite of the one you suggested they had.