I think it’s a matter of triage. They want someone eager and competitive, willing to bend the rules if it’s good for the company. They aren’t concerned about diagnosing or pathologising their interviewee.
Also if “The Wolf of Wall Street” or the song “White Lines” have any truth to them, cocaine abuse is rampant among the 1% (or the top 10% of the 1% and their children, whatever) and may even be encouraged. Cocaine addiction is totally in the DSM and some of the symptoms of intoxication and withdrawal strongly resemble certain (e.g. malignant narcissism, paranoia, histrionic tendencies, etc.) personality disorders on their own.
