You wouldn't be able to spend it on anything big as tax agencies will start asking questions how you bought this car or that house.
Would you really mind paying 10k USD if you made a million profit? I know I wouldn't if it means I made a million in profit.
Anyone who isn't automatically pricing in and planning their tax already is a silly sausage. In this day and age you can't fart without having your account shut down. Good luck winding up with a million dollars in sacks of coins.
You'll never run short of hotdogs and parking. Everything else will be impossible to obtain.