Hi all.  The pushbutton switch mentioned was probably once used to
start a coin piano or orchestrion (manufactured by Wurlitzer) playing
during "slow periods" when the establishment which had the piano(bar,
restaurant, etc.), wasn't getting any customers.  When that happened,
the owner would push the button (which was mounted in a discreet
location, such as under the bar) and start the piano to furnish music
"on the house",  or to lure in more customers.

I have only seen this in use once, to start a Seeburg coin piano
remotely (in the Musical Museum in Deansboro, NY before it closed).
I did not examine the piano itself, but I would assume the button was
wired in parallel with the normal coin trip mechanism.

Andrew Barrett