A person starts doing things to facilitate a stranger's life after briefly meeting at stranger's minimum-wage job and the Samaritan sees something they like- maybe the stranger's trying to make enough money for college (in my dream he was earning money for college and the security guard accused him of stealing even though he didn't)? Never anything big, never outright giving him anything, but just little things to help the stranger along- getting him an interview for a better job, etc. Maybe becoming a mentor?
As an ending, the Samaritan dies and leaves all of their money to the stranger, and s/he has a lot more than you'd expect. But that's the only time s/he's outright given the stranger anything; the rest of the time s/he's only provided opportunities that the stranger had to work for.

All ideas are free for the taking.