Not even just "get bored" but, just a plain matter of incentive. Salaries are a strong incentive against undermining your employer's work. Now, of course, there are people who are incentivized because they are altruistic and good at heart, but that's very difficult to measure. It's much easier to demonstrate aligned interests monetarily.

And in more sensitive agencies, if the government purchases software, they generally have the name and contact information of who they can arrest if the purchased item becomes or is found to be malware.