Had a young trainee start in our workshop a few years ago, first day it was the usual pristine, dark blue overalls ( still with the creases in ) and unbelievably shiny black steel toe cap boots on.
“Can’t wear them boots in 'ere son.”
“Eh?”
" They’re too new lad, ‘ere put these on."
as someone tossed him a knackered old pair that had been lying under a bench for months, covered in dust and split down the side.
" I ain’t wearin’ them, they’re minging!"
“Look lad, you’ve got to, they’re the rules.”
Someone pointed to the blue sign on the wall…" Safety Footwear Must Be Worn"
“See lad…worn, as in not new”
He believed it. 
Spent the next couple of days hobbling about in this old pair of boots. 
We had to tell him in the end.