Why doesn't Gary Grimes shoot? (spoiler)

At the end, Gary Grimes inspires the others to grab whatever rifles and pistols were left, break away, temporarily, from Culpepper, and stand their ground with the commune in order to get their guns back.

But when the fireworks begin with the cattle baron and his men, Grimes just stands there and does nothing as his friends all get shot and die. Only when the preacher refuses to bury them, does he get grow a set.

Is that the point? If so, okay, but...