I think their actions are similar to many corporations of today and I think it all boils down to one thing---greed. For me, one perfect example of a corporation that acts exactly the same way, if not worse, is Monsanto. Their chemicals are poisoning the environment and causing cancer and they continue to deny it. Big tobacco companies are guilty of producing a product that they know causes cancer and they deny it.
I think the women were resilient because they knew what caused their illnesses and they didn't want it to happen to other women.