> private companies padding out the contract not government employees

I have no references to back this theory up, but I feel like this is where most of the waste happens.

[Gov spend public money] -> [pay private company]

The government isn't incentivized to get the best deal for our money which results in overpaying or just flat out corruption. eg. I'll overpay my friend's company and they will kick me back some money for choosing their contract.

Actually, urban freeways around the world are getting ripped out. They are even looking at doing it to one in Detroit. I would be surprised if the freeways for the big dig are still around in 50 years let alone 200.

The big dig was one such "rip out" project. An above ground , elevated, urban free way was buried beneath the city.

It still goes through the city center with a lot above ground. Definitely better than before though