Buy you don't get it when something is backed by a commodity it will always be worth the commodity,
Not necessarily. Just ask anybody who has messed around with the Credit Suisse line of ETF and ETN stock products. Just because something is backed by a commodity, it doesn't mean the owners of the asset will necessarily do a good job of making sure there is always a correlation between the asset and the commodity.
For your reference, I submit to you TVIX: supposed to move at 200% of the VIX or market volatility indicator but seldom does and frequently goes down when the VIX goes up. This is because its owners (Credit Suisse) have found a way to legally manipulate money out of people who are assuming this ETN (Exchange Traded Note) will correlate with the VIX, like Credit Suisse says its supposed to.
Currently there is only a single company, but after proof of concept we are going to many companies sign up to the URO protocol, thus the buyers will simply go wherever the best service is provided and people who dont do a good job will loose salles, Credit Suisse is a single company, but if your saying its manipulated that's definitely fraud.