From the Super Mario Wiki
In The Super Mario Bros. Super Show! episode "Hooded Robin and His Mario Men", Mario, Luigi, Toad and Princess Toadstool, after having a brief encounter with Koopa Troopas in Sharewood Forest, and after meeting Hooded Robin, traveled to Sharewood Village; once at the village, Mario, Luigi, Toad and Princess Toadstool learned from it's inhabitants and Hooded Robin that the Sheriff of Koopingham had stolen all the Gold Coins in the village, which Mario, Luigi, Toad, Princess Toadstool and Hooded Robin vowed to get back. The Gold Coins were eventually returned to Sharewood Village, in a way; after an encounter with Fryguy, all the Gold Coins were melted, and this liquid gold was subsequently transported back to Sharewood Village through pipes and could be pumped out of the Sharewood Village water pump. To celebrate the return of the village's gold, a feast was held in Mario, Luigi, Toad, Princess Toadstool and Hooded Robin's honor.