Right; the commercial guys can use the code in their products, and so can the open-source guys.
There is nothing to prevent an entity from charging for a commercial app that was basically created via our tax dollars. This breaks the spirit of public domain.
No, the original code is still public-domain, but the derivitive products would be billable.
The GPL corrects that problem.
Not a problem. We all get to use the government code. The closed-source folks are happy because they don't have to expose their source code. The open-source crowd is happy because the government isn't favoring commercialism.
Public-domain is the key.