I don't think that's true. I was involved in some of the potassium-argon studies of the "Genesis Rock" samples brought back from the Apollo 15 mission, and trace element studies of the "orange soil" discovered by Jack Schmitt at Taurus-Littrow on Apollo 17. I can tell you we learned a heckuva lot about planetary evolution and lunar geology from those samples. "Useful science"? You betcha. I don't think we would have gotten those samples without a manned lunar mission to go find them, recognize what they were, and bring them back in sufficient quantities for analysis in a meaningful way.
I also helped with an experiment involving crystal growth in microgravity, which flew on STS-73 back in '95. We got a tremendous amount of data on diffusion processes for various dopants in a variety of media. That experiment could not be done on the Earth, or the Moon, because of the gravity gradient. It was a complex experiment that could not have been automated. It needed a researcher present at the system to make adjustments, take data in real time, and make appropriate changes to the setup and conditions. Very "useful science", I can tell you.
"I can tell you we learned a heckuva lot about planetary evolution and lunar geology from those samples. "
That and velcro makes it all worthwhile.
No offense intended but, um, what have those samples that were [brought back by a manned mission and analyzed in a meaningful way] done to provide a concrete, tangible, material benefit to the taxpayers who involuntarily funded it all (ALL the taxpayers; not just those who were employed to retrieve or analyze them)?