To the many comments, and my concerns to the tolerance of certain things, I would like to add that many people cannot efficiently nor autonomously handle (most or some of) their own frustrations and decide to vent them out in many ways, like throwing them to others, like when a simple cashier burdens a customer’s frustration for a (fair or unfair) complain, and littering is another way to do it, screwing “the systemic unfair world” or just looking to impact it in some way or another if they cannot handle a strong feeling of irrelevance. Consciously or not, is a coping mechanism that some people will use, while sometimes is something normalised to the point to be unconscious (people threshold for or concept of cleanness varies a lot).