Another conspiracy theorist who doesn't know a thing about the gold ETFs. To be sure, the arrangement with GLD is rather byzantine -- but there is indeed gold bullion in its vaults. You can't redeem your GLD shares for physical gold but Authorized Participants can -- 100,000 shares at a time (somewhat less than 10,000 oz of gold). Through the Authorized Participants shares are created (100,000 at a time) in return for deposits of gold bullion and shares can be redeemed (again, 100,000 shares at a time) for gold bullion. Any deviation in the spot price of gold from the share price of GLD (minus accumulated expenses) creates arbitrage opportunities that the Authorized Participants take advantage of, so the price of GLD is indeed tied to the spot price of gold. Audits of GLD are carried out twice a year.
There are leveraged funds that trade gold futures, not gold bullion, but the big 1x funds like GLD do have physical bullion.