They can, sorta.
I was involved with a Sydney Airport exercise in 2000 that involved the public (SES volunteers- note not SAS, different mob).
We used an F27 as the medium sized turboprop and an emergency was simulated. Fire crews, ambulances etc were involved as well. The "pax" did the brace position and used a door to get out. Whilst not jumping out of a window it served the purpose.
So, in Sydney, if you want to practice this you can join the SES and volunteer for when the next Airport drill is on.
SES = State Emergency Services. A fine group of volunteers who clear roads after storms, put tarps on roofs, participate in searches and rescues.