So the only sense in which it actually makes sense to sue is for a poor quality product.
What about anti-trust? Don't they have anti-monopoly laws or something in the US?
We do indeed.... but we also have this:
https://en.wikipedia.org/wiki/Sovereign_immunity_in_the_United_StatesOf course, the Fed is not officially part of the government, so it may not be shielded by that.