I think to some it is just a game for them so they have stories to share with their friends.. to others, they think it's love but they really don't know the person that well yet.. some might even just be looking for a rebound after a breakup so they know that someone else is interested in them, even though the last person wasn't.. I guess we all have our own reasons for why we act the way we do and this unfortunately means that sometime our feelings will get hurt by someone else..