Here's the problem: On Monday vagrant comes up to you in a parking lot and asks you for money. Later you see the vagrant buying booze or cigarettes with the money you gave him. On Tuesday day the vagrant comes up to you and instead you buy him a loaf of bread and then later see him buying booze and cigarettes with the money that someone else gave him.
On Wednesday the vagrant brings along a dog and asks for money to feed the dog or take the dog to the vet. On Thursday he asks for a bus far to visit his sick mother in hospital.
At what point do you stop giving money to vagrants?