We live in a world filled with speculative bubbles. You have speculators to thank for their price discovery efforts. This enables you to pay the "true value" of a given commodity at a given moment in time.
I disagree that speculators have any role in discovery of true value - on the contrary, they mask true value and ensure our markets are inefficient, panicky, and volatile.
The only benefit I can see is there is an overall increase in liquidity but the cost of that liquidity is quite high.