Draft = you get called by scheduling at home, on a day off, and asked to fly a trip. The trip pays 150% of normal pay. Volunteer = you tell scheduling that you'll fly extra - when they call, you got to go. 150% pay again.
I think most guys could sympathize with a guy in that position, but that doesn't make it the right thing to do. The problem 99.5% of the time, is guys adjust their life stlye (spending habits, cars, houses, boats, etc) beyond what they can support with normal pay. Financial planners suggest a buget that includes your wife not working, so if or when something comes along (kids, medical bills, etc), you can exist without having to downsize homes, etc. Nothing wrong with the wife working - just make the buget work without her working.