You need to understand how government buys software. Nobody prevents any company to propose the smallest possible price by utilizing OSS. Yet this is not happen

You need to understand how government buys software. Nobody prevents any company to propose the smallest possible price by utilizing OSS. Yet this is not happening because all of those pushing the idea do not really do anything and actually help their governments locally. Another important factor is that gov workers rarely have enough skills to run OSS software, they are understaffed. And, it is difficult to integrate OSS with the existing systems. Finally there is a question about responsibility and control. If you get a 0-day in OSS, who will patch it and who has the rights to push that patch? It is about managing risks.