In short, who cares?
Note how badly this policy failed:
"If anybody has any idea of hoarding our silver coins, let me say this. Treasury has a lot of silver on hand, and it can be and it will be used to keep the price of silver in line with its value in our present silver coin. There will be no profit in holding them out of circulation for the value of their silver content"
Silver dimes and quarters are worth several dollars now, so it clearly was worth keeping them out of circulation.
Price manipulation is not worth the cost in the long-run.