I consider myself a pretty nice person and so do my friends. i think i would help a mother/ soon to be mother if she needed help with a flat tire, i also think i would help the kid and mostly anyone that just seemed helpless in their stuation. See this is where I think society has problems. the kid in the store, if his or her mother would have been paying better attention, or the kid just ran off. or the homeless people as someone stated earlier, I'm not trying to say that person is careless but how the homeless people got that way, because you give so much and it will never be enough.
Or if people were just plain smarter (of course then we'd be stuck with a raising bar and no one trying to meet it). But to get back to the topic i would if they seemed, kind of helpless.