Quote from achilles28:
Speculators are chiefly responsible for price discovery, liquidity and bear risk for producers/hedgers. Non-speculative markets - dominated by producers and wholesalers - are often manipulated to the detriment of consumers, with higher spreads, and the market itself far more illiquid. In non-speculative markets, there's no bid in periods of glut. And no offer, in periods of drought. This distorts prices far below and above fundamental value, which is then acted upon by producers and consumers who interpret those distorted prices as true market indicators, and over-invest in supply/capacity, or alter their consumption/production habits. This creates further distortion as when the glut lifts, most producers have changed their fields to another crop, or new business were created that depended on cheap supplies of xyz. Speculators smooth out the price cycle, recognize value where suppliers/consumers want none, and ensure orderly future production/consumption around realistic prices.