Those trees, most assuredly, belong to someone and often the fruit is waiting to mature and the owner will sell all on the tree, or they are waiting for family to come and share in the bounty. So, sometimes what looks like "free for the taking" is not. Even way out in the campo, people know whose tree belongs to who. It's a shame that often the early fruit falls to the ground and spoils, but it all depends on the owner.
I have a small finca that I let a local guy grow a crop on and he is supposed to look after my avocado trees. I drive by every couple of weeks just to check the place out. Out of five beautiful and bountiful Avocado trees I'm lucky to get a couple of dozen fruits because those locals rob the trees at night or on Sunday.
Here in Jarabacoa I think there is probably less hunger as this area produces huge surpluses of veggies...etc however yes I know children that only get one meal a day. The government also provides food for plenty of poor people as well.