Paying the guys keeping the burning parts of your country in check enough, so that they keep doing it seems like it would be up there with "maintaining roads".
More likely, there is a bit of focused lobbying being done to suborn the few decisionmakers involved with this, so that a company that contracts firefighting services to the government can grow their contract.
I don't know exactly how it works in California. I know there is a "California Conservation Camp" program that pays inmates $2.90 to $5.12 per day while in the camps, and $1.4 per hour fighting fires, but I don't know if they work with only state prisons or if private prisons get in on that too.
Maybe the cost savings there are enough to drive this dynamic.
The recent railroad strike fiasco was a perfect example of how things are really ran.
Doesn't seem son hard...
https://www.govexec.com/pay-benefits/2015/02/17000-federal-e...