I too think that this is something you must decide for yourself and do whatever is right for you.
When my son was hungry I'd have him over for dinner or take him somewhere and buy him lunch or dinnner and maybe something to take home. I'd do the same for any hungry person and I didn't have to trust him when we were on neutral ground.
I bought him groceries a few times, until I discovered that he sold them too the moment I left.
It's a shame a mother has to think about this, but like you I'd hesitate to give him money for any reason knowing it would never make it to be food on the table.
My heart to yours, Hugs.
