Scrubs don't look nerdy (well, not too much) in the appropriate context. I hate when I have to make errand stops on the way home but the scrubs really do look nerdy when you see people wear them in social situations...actually they look pretentious rather than nerdy.
If one were to wear them for a system wide orientation, that would seem to e the same as if a medical student wore them for the first day - what's the point? Scrubs are to serve a purpose, they are not an ID card as to the wearer's potential career.
But if you want to wear them, go ahead - just don't say I didn't warn you that others may look askance at you.