The biggest reason is, what is the downside? Working with US spy agencies as an american on american soil you don't risk getting thrown into jail for the rest o

The biggest reason is, what is the downside? Working with US spy agencies as an american on american soil you don't risk getting thrown into jail for the rest of your life and the biggest downside is getting caught and fired but you are being compensated with money anyways so why would you care. Working with foreign governments is much more risky but I am sure they have tried and do have agents working in large companies such as google.