I just think it's weird. If part of my coworkers' job was involved landing in the Siberian wilderness and they carried a gun to protect themselves, I wouldn't go out of my way to disarm them and then congratulate myself for it. Not even if it was David.
The very idea of guns make some people crazy - for or against, usually against.
Would the spray can be safe for 0 atmospheres (in emergencies in the capsule?)
I would expect that they are puncture resistant, so able to survive > 1 atmosphere change, and I imagine if you're at 0 atmospheres if you can smell the bear spray it's probably not actually your biggest issue.