My SCUBA instructor did the same thing - all pink diving gear. It was too big for any of the women he dove with and none of the guys wanted it (or it would at least be quite noticeable if they did take it).
Except in a public company, the final word isn't work the IT supervisor (or even CEO) - it's with the shareholders.
The correct answer (and what I have done in the past) is to call internal audit and run it past them. When it bubbles up that not having controls around powerful accounts is going to show up as an exception on your SEC filing the tune will change.
It is everyone's responsibility, network admin up to CEO, to protect the stakeholders.