Keeping with the times

Is there such a thing as an appropriate 'work' costume? I understand that it is casual friday after all... but some people.
I wish I had an Iphone so I could have been sneeky and snapped some pics... but I don't.

But there was a 250 pound woman dressed as a sexy kitty cat at starbucks.
A 40 year old pirate wench in line at the bank, wearing fishnets and hooker boots. and a corset.... shiver up spine.
and a geriatric sexy - nurse... litteraly, this nurse was old, too old to be wearing fishnets anyway... borderline retirement!!

Maybe its that costumes in general have gotten grossly inapropriate....

I do however think, if you can add sexy to the front of your costume idea, then it might not be right for work. Just saying.