He 'profited by' his experience/mistake. [=he learned something useful from his experience/mistake]
The book can be read with 'profit' by anyone who wants to understand how the system works.
We sold the house 'at a profit'. [=we made a profit when we sold our house]
(..) Take deliveries at the front door and sell it out the back at a discount. Take a $ case of booze and sell it for $. It doesn't matter. It is all profit. Then finally, when there is nothing left... ... when you can't borrow another buck from the bank... ... you bust the joint out. You light a match. (..)1990 Goodfellas