Thanks for the correction Shinta. I meant that I believe (to a degree) selflessness is a quality that heroes should have.

I think of it as a tradeoff. Lots of resource go into making a Hero, and it'd really be a waste of resources for each of them to die saving someone crossing a road, for example. They need to know when to self-sacrifice and when not to, to be an effective hero. Of course, most would see this form of discrimination as being very not-hero-like.