As impressive as your Monday morning quarterback degree is, the Corps are doing all they can to minimize the damage both locally and downstream. There is a whole lot more that must be taken into consideration than your pleasure boating or camping. People downstream loose everything they own and/or DIE when flooding occurs. The local lakes feed into a much bigger river system that has a major impact on a very large population.
Not to mention the local lakes were designed ENTIRELY for flood control. Fishing and the recreational aspects are just a bonus.