Where did uncle Tony get all that money?

After my dad died in the early 80s my mom started going to the VFW. There she met a man named Anthony Carpetto. They struck it off and became a couple. They never married, nor did they live together, (they were of the Greatest Generation, that kind of thing just wouldn't be proper) but after Tony developed Alzheimer's disease my mom took care of him until he suffered a stroke and died. Tony was a retired house painter who had worked for the federal government. At one point, just at the outset of the Alzheimer's, my mom had to take "Uncle Tony" around to several banks because he needed to break up his bank account because the FDIC only insures up to $100,000.00 Yes, the old bird was loaded. He spent a lot of time hanging out with friends at a pizza parlor and at an auto shop (Vito's Auto Repair). He lived very frugally and was a notorious dumpster diver. His apartment was full of all kinds of junk, lamps, TVs, radios, oddball items. It looked like the house in Sandford and Son. However, it wasn't in Watts, it was in Northern New Jersey. After he died he took care of my Mom and she never has to worry about money. He had a couple of kids and they got taken care of too. His money has come in handy a couple of times when I have been in a spot. He was a nice, quiet old guy, a WWII vet who saw hellish action at Normandy and in the Battle of the Bulge and spent time in a POW camp. He got veterans benefits, his wife died in the 60s and he probably got some insurance money and he had a pension from his job and lived furgally but I can't figure out how he aculated what I believe to be well over half a million.