I was wondering the other day why toy theatre performers sometimes wear paper hats. I assumed it was a tradition of some sort, but I didn't know the details. I had a hard time of it finding the answer, but I was persistent, and finally tracked the information below down. Now, it makes perfect sense!!
In The Tenniel Illustrations to the "Alice" Books (Ohio State UP, 1985), p. 18, Michael Hancher mentions several of Tenniel's cartoons for Punch that featured paper hats for workmen (Ref:July-Dec. 1853, p. 169; 6 April 1861; 22 June 1861; 5 Sept. 1863; 4 Aug. 1866)
In the 19th century, square or box-like paper hats were worn in a number of trades: by carpenters and stone masons in particular, but there are references to their use in other trades, as well. Tenniel's Carpenter does in fact wear a carpenter's hat (which seems to have been folded in a different way from any printers' hat I'm familiar with: note the double diagonal creases, characteristic of the former but not the latter). - Terry Belanger, University of Virginia
"...paper hats were made and worn by carpenters, printers, and other artisans to keep sawdust etc. out of their hair..." - From The Chronicle of the Early American Industries Association, Nov/Dec 2003, PAPER HATS
Even later, they were known..."Paper hats were once as common in a pressroom as ink..."