Well this guy in person is fucking rich. He has people that do send him food and basic amenities, so I see no reason why I have to reason of being in his shoes or rather trying to choose his type of lifestyle. I think his reasons of staying in an island is due to frustration he encantered during his days in the city. Staying out of stress of life and humans' congestion is quite okay for him.
Exactly he is very rich, I tried to go through some articles and I found that stated that and it is true that someone sent him food supplies and so on.