He lives in Nevada, so no state income tax. And I may be wrong, but I think for big winnings the casinos take the federal tax off when you cash out, or at the very least give you the proper tax forms.
This. It is a non-traditional career to be sure, but maybe he is willing to take the risk to have a lifestyle he can enjoy. He is a young guy. Seems to me that just like a lot of fellow millennials he has found a way to earn a living without having a traditional 9-5 job.
I am enjoying his run, but I also enjoyed Ken Jennings, Julia Collins, and the other long run champs. (well, not Matt Jackson and Arthur Chu) However, I do feel for the contestants who are up against him- it must be so disheartening to finally make it on to the show and find out that you have been paired against a record-breaking player. If his run continues into the new season, all of the incoming contestants will be familiar with him, and maybe then someone will come along who can beat him at his own game, with lots of correct answers and strong wagers.