If he had a gambling addiction he would have gone bankrupt a long time ago. If he is still a millionaire then he is in good control of himself and his money. I could be wrong, but it seems to me more and more that his winnings are a kind of advertising campaign aimed at attracting new users to Stake.com. If that's the case then it turned out to be a very successful campaign so talk of him winning has been going on and on.
That would be really true. I think that Drake also has his own financial manager or people who would organize his assets, advise him stay in his limitations and the likes. And if this is just an advertising stunt then they really did a good job because the name of stake has been loud ever since Drake came into the scene.