Even non-delivery speculators are buying and selling goods.
Suppose a non-delivery speculator Steve purchases September grain futures from Farmer Bob, and sells them to Charlie's Cruise Line a month later. You might not think Steve was actually buying or selling grain, but clearly Bob was selling grain, and Charlie was buying it. So what else could Steve have bought from Bob or sold to Charlie?
The point remains: the only way for Steve to make money is to buy things cheaper than he sells them. This will raise prices then they are low, but reduce them when they are high.
“Even non-delivery speculators are buying and selling goods.”
Churn and burn speculators do not take delivery nor do they ever have any intention of taking delivery, so what are the “goods”? Can’t be the commodity itself.