There are really two different points of view about whether patients should be compensated for the use of their cells in research. On the one hand, Skloot evokes a great deal of sympathy for the Lacks family, as they are poor and suffer from ill health in part because they have difficulty getting access to medical care and lack the knowledge that allows better-educated people to work the system. The notion that Henrietta's cells underpin so much medical research, and that the HeLa line is responsible for millions of dollars in medical grants, without Henrietta or the family benefiting seems disturbing. This is exacerbated by the fact that "informed consent" which underpins the use of the cells for medical research is especially problematic for a family that is not sufficiently well educated to understand the nuances of the issue.
On the other hand, there are good reason why researchers should not pay for tissue samples. The sale of any body parts, even ones which regrow, is a slippery slope, and could lead to the horror of poor people selling parts of their bodies, voluntarily or involuntarily for use in organ transplants or medical studies, or being compelled to become test subjects in order to get medical treatment.
The current NIH settlement, in which the Lacks family sits on a board determining the uses of the cell line, but without financial compensation, seems to me a good compromise, giving the donor and family the right to determine how the cells might be used without actually offering financial compensation for them.