A citizenship program would be kind of useless in that the money is more than enough of an attraction. Think of it this way, most of these guys come from second-world or former east block countries where the average income is along the lines of $6K a year or something. Suddenly, they can go make $50-80K in a year working for a contractor. When they do go back home after a couple years, they are literally set for life if they work it right. Make no mistake, the TCNs do make considerably less than US personnel do, the company I work for pays about 40% less to TCNs.
Oh, and as far as pay goes, it usually will work out to be around $20 an hour for a US civvie. They pay a base wage hourly, but then add on a "uplift" package that includes a pecentage for overseas living, a percentage for shitty (not their word) living conditions, and a hazardous duty percentage. All that on top of your base will bump you up to the $100K+.