This is shady, but artists should get paid if their work is heavily sampled.
>attempting to create something worthwhile from it
You say that as though the sample itself is not worthwhile or valuable. There are plenty of modern songs for which the only reason they are popular or sound good is that they sample older tunes. And it's simply not easy to create a good-sounding, catchy sample. So whoever owns it deserves to get paid, and it's no one's fault but the original artist if he or she sold off the rights to it for a pittance.