I am retired military and now have a civil service job. I see absolutely no reason to retire early from a civil service job.
In the military, I moved 13 times in 21 years, deployed 3 times, wore chem warfare gear and gas masks (several times for real), got 6 anthrax shots, worked 24 hours straight twice, worked 12 hours often, worked 6 or 7 days a week sometimes, got calls at home at all hours of the day, got my leave and life all jacked up by Slobodan Milosovic and Saddam Hussein, worked all holidays, weekends and hours on the clock, worked shift work, worked and slept in buildings that were later blown up by terrorists, and got mortared daily in Iraq.
In civil service, I get all weekends, evenings, and holidays off, I get every other Friday off, my schedule is set in stone, I never miss lunch, can take leave whenever I want, and I will probably never move. It is the easiest thing in the world and I really don't know why anybody would want to leave it. Even on my busiest and most stressful weeks, I still feel like I am semi-retired.