I'm a full-time employee. Managers and government benefits are a pretty big part of it. Work hours are very flexible (some roll in at 6am, others 10am), lengthy vacationable time, etc. Like morga3sm said, we want to do things correctly.

It has its downsides of course: getting a TS security clearance can be stressful, but that goes away afterwards; not being able to tell your SO what you do other than high-level stuff; career advancement and progression can be a long process and you basically know where your salary is going to go when you first start (because it is standardized); and so on.