Preliminaries typically require very little funding, which makes them easier to do - can often be done with time between other studies, and grad students are cheap.While I agree with all you have said, I still don't believe many graduate students would wish to lend their name to such a study, much less get funding for it.
And I still point out that I am not agreeing with the OP, just stating science would never look askance at anyone saying they wished to conduct such a study. I also believe a preliminary would have as much chance of being funded these days as a more rigorous study.