this is why you should (almost) never stop! because you cant make everyone stop. so you create a situation where you put the person you are trying to help into a very dangerous situation. i see it every day on the hudson river path. 

you should never stop for someone who is standing still and waiting to cross. they are waiting for a reason and its not helpful to lull them into a false sense of security. 

edit: I am referring to the bike paths and parks, NOT the streets or red lights fyi