It amazes me even more when some of them claim they were in the military at one point or another. I don't doubt that some of them were at one point or another, but their platoon sergeants must have given them a really bad time while they were in for them to carry over such hatred.
When you scratch the surface of a "I was in the military and I HATE THOSE BRAIN-WASHED BABY-KILLERS!" person, you'll usually find someone who--
a) got kicked out for one reason or another or
b) someone who couldn't hack it but managed to make it to the end of his four years as the platoon b*tch; scrubbing floors and painting walls because that was the only thing he couldn't screw up (though, occasionally, he could find a way). People like that resent their betters for 'not giving them a chance,' even though they've been given multiple chances and keep failing.
I'm getting rid of a type b later this month, and good riddance.