Yakuza 4

Throughout Kamurocho, you’ll notice green glowing items lying beside garbage bins. Trash comes in all sorts of types. You can find trash bins with trash lying beside them through the streets of Kamurocho, between alleys, or in parks.

Pick up 20 pieces in order to unlock the trophy. Trash picked up doesn’t need to be in your inventory. You can discard them or put it in your storage afterwards. If you keep the garbage you collected, you can convert them into “cash” at the Eco-Man in the sewers. You can use the points you have earned from recycling the garbage to buy items in the sewers.