If we don't burn the crude oil in the supply stream there will be no profit motive in maintaining the infrastructure and it will be shut down to preserve economic stability; if allowed to atrophy it will be lost as a backup strategy and we will be in a new crisis of supply as our demand for alternative fuels outpaces our accessibility and there will be hundreds of stories written about the "Sludge Belt" where old oil fields are slowly turning to tar pits.
Regarding crude oil: I happen to think it's a pretty valuable resource (plastics!), and we shouldn't be just burning it.