While the dude who invents the drug that saves my life is doing far greater work than the dude who makes it possible for me to buy that drug at the pharmacy two

While the dude who invents the drug that saves my life is doing far greater work than the dude who makes it possible for me to buy that drug at the pharmacy two blocks away, they're both doing good work, and both a net gain to the world. Why disrespect either? There are genuinely useless, parasitic, and net-negative people out there, but none of the proposed examples (bankers, pharmacists, Google) falls into this category.