This isn't really a rebuttal to their point. The 70% they quote is for the salaries of all health care workers. Presumably this includes the phlebotomists, the lab techs, and all the other people who need to do their jobs in order for those daily labs to happen and the results to come back. Depending on how loose of a definition of "health care worker" they use, they might include other hospital support staff (janitors, accountants, etc), equipment/disposable manufacturing workers, and/or bench scientists who design and optimize the labs in the first place. It'd be nice to see a more specific definition of whose salaries exactly they are including in that figure.
You're right. And I'm sure their definition was quite loose.
But posters were confused because this article is about rising physician salaries. Using that 70% number is quite misleading, and I'm sure intentionally so.