If anything, fast quantum calculations would make an even bigger difference in materials science than in drug discovery. That's because druglike molecules have been studied a lot, so classical approximations (though limited) at least exist.
"Simulating Physics with Computers", International Journal of Theoretical Physics, volume 21, 1982, p. 467-488, at p. 486 (final words) [0]
The limiting step in being able to manufacture any small organic molecule from raw materials is algorithmic. Imagine a molecule printer that can compile a set of synthesis steps for an arbitrary molecule via simulation. It's not as far-fetched if we can simulate hypothetical reactions easily: http://www.nature.com/news/organic-synthesis-the-robo-chemis...
The other parts of what you're saying are true but don't depend on what happens in quantum computing, they're just part of the for-profit drug industry. There are government and philanthropic drug hunters today who are doing good work, and if they had quantum drug discovery, they would be able to do even more.