One of those lightning rod theological topics discussed at seminary is "universal salvation." Boiled down, universal salvation is the belief that salvation (being saved by Jesus, going to heaven, participating in the resurrection, etc.) is available to all peoples, no matter what. That takes care of the "why."
Yet the reply was always there: "But how can people who don't believe in God or who do terrible things go to heaven?" Right now, I'm not trying to descend into these debates, but simply to put them out there, and try to turn a corner and look at this topic in a different light. (By the way, there are scriptural passages that support both limited and universal salvation.)
That is, I think we're stuck in the "who" and "how" questions of salvation. Instead of going around in never-ending circles of theological argument and abstract thought, let's ask the more important question about our salvation: "what now?" It's far better to be a disciple of Jesus and "go and do likewise" than to descend into the Pharisaical trap of theology without a purpose.