It stands to reason that a guy going into the military in WWII could have used one of these knives during the war.
One did, it is documented on pages 138-139 in Hunt's "
Randall Military Models", but to make a blanket statement that there was some sudden flurry of purchases by the newly formed UDT in its infancy is a dream at best. Even the inference this took place is disingenuous without any evidence to support it.
Most of the maybe ten or so I have seen were found in atackle box or kitchen drawer. They were not very popular being limited in their use and the expense. That was a pricey bottle opener back in the day!