These are themas that european animation movies tend to illustrate really often. Here is a selection of 4 movies treating the subject brilliantly and with some great and strong graphic style
Let's debate on the message/morale of those movies in the comments as they might be interpreted in many different ways.

La marche des sans-nom
Directors : Lucas Vigroux, Nicolas Laverdure, Jean Constantial
Production : Supinfocom