[harimau777]

A lot of people prioritize working on software that intellectually stimulating. If someone is an expert in medical simulation, sonar, VLSI, etc. I don't think that they would consider developing plumbing software to be an equivalent job.

[smeej]

If they're an expert in medical simulation or sonar, aren't they likely already working for a relatively small company, and one that's located near, say, a hospital center like Boston, or an ocean? That's still a service within their locale and to their local community, even if the local community is also engaged in specialty work that benefits the whole world.