Yes, Brannan cornered the market before he sold the shovels. Selling shovels is not that profitable if you skip that "Step 1".
> he owned the only store between San Francisco and the gold fields — a fact he capitalized on by buying up all the picks, shovels and pans he could find, and then running up and down the streets of San Francisco, shouting 'Gold! Gold on the American River!' He paid 20 cents each for the pans, then sold them for $15 a piece. In nine weeks, he made $36,000."
If there's a goldrush, you get rich by selling shovels.
... unless there are already 200 shovel shops next to each other...