Earlier quoted context omitted.
At least at Microsoft this would also get you fired pretty fast, according to the infamous standards of business conduct.
At most of the big corp. Somewhere in my employment letter it says, you are representing company outside of workplace and work hours as well (that is in personal life too). I can be fired if I bring disrepute to company anytime - ex. involved in a weekend nightclub drunken brawl.
The very concept of "bringing disrepute" is a slippery slope, and shamefully medieval.
Edit: I'll clarify. The problematic issue is the ambiguous, subjective threshold at which activities become "disreputable." Ambiguous, subjective standards like that should not be grounds for dismissal. They are too easily abused via "selective enforcement".
Of course, in many firms, employment is entirely "at will," and subject to employers' most capricious whims. This is not a good thing; the subjugation of one's employment to another's whim is an oppressive imbalance of power.