[ceejayoz]

I suspect people fall on grenades more to save their friends in the blast zone than some ideal of patriotism. There are cases not involving military/combat as well, like https://en.wikipedia.org/wiki/Lawrence_Oates.

You appear to have constructed a weird, intentionally specifically narrow definition of altruism as a strawman. Congratulations on slaying it.

[jdmichal]

Specifically, one is either an egoist for receiving any type of reward, intrinsic or extrinsic, and regardless of intent, or an idiot otherwise.