There are many reasons for people being homeless. You could get a terminal illness. Someone could steal your identity today and you would be living in a box in your neighbor's driveway tomorrow..
If you were homeless with no friend, family or resources to fall back on, a stranger sees you and takes pity on you, and this person gives you a $5 bill. How would you spend it? How would you manage your newfound wealth?
Any one of us could be one step away from living in a homeless shelter or eating at a soup kitchen or looking for food in a trash can. There is an old saying, 'The pride goes before the fall." Never be too proud to help a person who is down on their luck, because you are a flip of a coin away from joining them tomorrow.