Several thoughts....
1) I agree with the on their time their rules theory, after all they are paying you for representing them.

2) It is sometimes easier (not necessarily better) to get forgiveness over permission.... however since you've already asked you could be in direct opposition to a directive. This is shaky ground to be standing on.

3) Is this the hill you want to die on? Often I ask myself this when I come up against things I want more than those around me. So, sometimes even on my own time I wear trousers to accommodate those around me. People are more important than clothing (yes, even kilts).

Cheers,

Marshal Moroni