"Only because?" Strongly disagree. I think it's actually because there are human beings who work at FDA who, like all human beings, have had loved ones suffer, get sick, or die. Everyone (presumably) wants safer and more effective treatments for sources of suffering, and e.g. interpreting drug trial data is really fucking hard, even for the people who create the drugs.
Separately, yes, there are also instances of straight-up corruption. It's totally divorced from reality to suggest that collaboration is "only because" of corruption though.
I believe people at the FDA and NIH are allowed to have financial interests in the drugs they regulate[0]. I'd bet the SEC doesn't permit that. That would probably explain the difference.
The "only because" relates to why they don't fight the regulators. As in "why fight them when you can have a revolving door agreement where they get cushy jobs in your company after they leave the FDA". In other words, I am not implying that there aren't other reasons for collaboration with the FDA, I am implying that there isn't a culture of "fighting regulations" because there is instead a culture of manipulating regulations. This in no way implies that there isn't also good collaboration.
Separately, yes, there are also instances of straight-up corruption. It's totally divorced from reality to suggest that collaboration is "only because" of corruption though.