The government isn't shy about spending on defense, it is shy about spending on people. GS and GG pay scales aren't that great when compared to industry positions. Consider that GS-13 is often the max for SMEs in many engineering disciplines across the fed until you get into PhD territory (to stay technical, management roles more easily go up to GS-14/15). GS-14/15 if you're in cyber and somewhere like the NSA, maybe. And while that's better than GS-13, you're talking about capping at around $200k or a bit better in high cost of living areas with skills and clearances that could make you much more in industry.