I think people get the addicted because of the profit that gambling could bring to us. It's really easy money and fast.
Gambling is addicting normally even the main reason is profit or entertain we do have our own taste of satisfaction.
Most of us are satisfied with earning that much and others are liking the way their lives are depending to gambling and others are making it as their business.
It differs from person to another - even twins are not the same in terms of emotions and intellect. After all, as long as the person is not harming us, let that person do whatever he/she wants and we shall not critize.