I realized something while looking at the rules for 100%: you have to explode every barrel.

And at the very beginning of the game, there is a barrel spawner.

There is an infinite amount of barrels in the barrel spawner, and you have to explode every single one.

Take this as you will.

You only have to explode the barrels that you spawn, so if you don't spawn any barrels you also don't have to explode any. "If you duplicate an item, that item must also be held and if it's a barrel it must also be exploded"