And what happens in the United States with the IRS, if one does not turn a profit on pool due to tax write-offs and deductions for expenses/costs, the IRS does not recognize it as a profession and it becomes a "hobby." A hobby does not let you deduct expenses that are more than your income.
Believe me when I say the expenses on the road in the early 2000s were hefty if you wanted to eat well and sleep in a decent hotel. Entry fees, travel expenses, hardware purchases and tune-ups, they add up. Even when you cash in the big tournaments, you're so suck from the ones you did not cash in that you never, ever turn a profit, unless, of course, you win, place, and show on a regular basis to offset the exorbitant costs to play pool professionally around the world, two, three, and four times a month.