Living the Good Life

I've played poker for decades. I've known hundreds, thousands of punters, amateurs, pros and semipros, winners and losers, the sublime and the simple, the saps and the geniuses.
And there's this big question hovering around the poker world that's bothered me for a long time.
They come; they go. Some last, but most seem to fall off the end of the pier. Never seen again.
Why? This word keeps banging marked cards a dull, thudding bell in my brain. Why do they vanish? Isn't this "the good life?" No real job. No responsibility. Easy money. Pick up and go where you want, when you want. Have cash, will travel.
So, while in Vegas I got in touch with a friend, a pro "with legs." We had a leisurely dinner and a long chat.
My editor likes me to personalize my protagonists, so let's call him Max. Max plays mainly Stud, but he'll sit in a game of Hold'em if the field looks soft.
His home is Vegas but he follows the tournament circuit - not to play in the events but for the side action. He says he makes the lion's share of his income in these circus-like gatherings since the joint tends to be filled with players who just aren't as good as they think they are - and many arrive seriously bankrolled.