Some people, some gamblers are extremely sick in their addiction and despite the fact that they have not food to put on the table they go and borrow money from their relatives in order to gamble. I think these type of persons need a huge professional help, be it by gambling rehab centers or state sponsored help. They are victims of their own addiction I know though I think it is better to help such persons as otherwise they become a huge risk for the society they live in. Personally I have gambled money I could not afford to lose and there is no more worse feeling of regret after doing so, that is why I know help is definitely needed for such people.
It is hard for me to believe that a hungry person would decide to give away the money they borrowed from someone to play instead of going to get some food. I understand what you are talking about but it seems to me that such cases are really very rare these are isolated situations. A person will always first think about getting something to eat and where to spend the night these are basic needs that will always come first.
Yes there are players who lose a lot and maybe even take things from their parents' homes to sell them pawn them and keep playing. But in that case again their basic needs like having food and a place to sleep are covered if they can do it at their parents' house but this is definitely a problem that should be addressed. Personally I have never seen such players in my life and have never had such acquaintances so in my view there are actually very few of them.