This would appear to be part of a wider issue, that of image. Image is everything in FE and rightly so; it is selling a product. I would be cautious though about controlling staff beyond their professional duties.
If, as might have been the case, your actions had some impact upon the college, however tangential, then as a manager I would point this out. In that respect, as an employee who may wish to be promoted one day, I would be cautious about my behaviour in and "around" college.