I read some anecdotes about pro cycling teams during the Tour de France who would take doors off the hinges and put them under mattresses to firm them up. Privacy wasn't that big a concern since they were likely taking a floor or wing of a hotel for the night.
tbf, on the TdF by nature you're often staying in small and medium-sized towns with a huge mixed bag of accommodation choices. Air conditioning was often not even a given.
Huh thats pretty interesting. Might as well pile up sheets on the floor and sleep there if it comes down to that.
Especially the monster pillows. yuck. first that gets tossed on the floor.