If nothing else, because it would be prohibitively expensive. Globally, something like 70 million barrels of oil are produced per day. The total value of all barrels produced in a year varies depending on the price of oil, but at a highish but realistic $100bbl, you're talking about two and a half trillion US dollars per year. If you were to reduce the supply by introducing a 'buyer' (read: subsidy to defer production) for some large percentage of those barrels, then the price would go even higher; this project would probably cost more than the entire global military budget combined, with no immediate practical or economic benefits.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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