This is very, very true. In fact, Heinrich et al wrote a wonderful paper decrying this very problem.
humancond.org/_media/papers/weirdest_people.pdf
Unfortunately, its not going to change, because of the pressures on academics to publish, publish, publish inclines them to take full advantage of these samples of convenience.
Its actually even worse, because the majority of psych papers are based on American psych students, so there's not even much of a good geographic spread in the ridiculously limited samples psychologists use.
humancond.org/_media/papers/weirdest_people.pdf
Unfortunately, its not going to change, because of the pressures on academics to publish, publish, publish inclines them to take full advantage of these samples of convenience.
Its actually even worse, because the majority of psych papers are based on American psych students, so there's not even much of a good geographic spread in the ridiculously limited samples psychologists use.