Yes this was what they used because the currency system was in chaos. Bread might cost one price at one place and cost thousands more at another. Looting was a risk also like all wars.
"During World War II, the Japanese issued Military Gumpyo Pesos (PHJ) at par with the Philippine Peso which continued to circulate; however, Philippine forces had withdrawn into the jungle, and issued their own Guerilla Pesos (PHG), redeemable in paper Pesos after the war was over. The Japanese made use of the Guerilla Pesos punishable by death, but since this would have led to the collapse of the Philippine economy, local Japanese authorities acquiesced and often allowed the Guerilla Pesos to circulate. During the war, the Japanese Military peso depreciated relative to the Commonwealth Peso with the conversion rate declining from 1.25 PHJ = 1 PHP by May 15, 1943 to 1.44:1 in June 1943, 20:1 in July 1944 and 120:1 in January 1945. The Ballantyne Scale was adopted by the Congress of the Philippines in 1945 to calculate these conversion rates." WikiAnsweres