Certainly if we were looking at 100% solid objective evidence then what you suggested is all we can conclude. I don't know about you, but I don't make decisions only on a 100% chance of truth.

This would be evidence for the attitudes our reporter is attributing to his subjects... if the reporting was unbiased, not in the sense of "lacking an ulterior motive" but in the sense of "proportionately likely to report each option". (Technically individual data points are still evidence, but potentially much weaker; aggregated ones can in some circumstances be negative evidence.) Given the reporting slant and indeed the fact that we're discussing journalism, however, I don't believe we can rely on the provided interpretation of events. I'm willing to take the article as strong evidence that the events themselves did occur -- we're not talking tabloid journalism here -- but that's all.

More generally, I think it's unreasonable to expect perfectly restrained private behavior -- and that is what we're talking here, if you accept that upper-echelon Wall Street social circles constitute a subculture -- from people regardless of their wealth or power. Their behavior as regards the disposition of that wealth and power is socially significant, as to a lesser extent is their public facade. What they do behind closed doors doesn't concern me.