Its imperative that you speak up. Managers who have made a career out of the government (some would say they’ve been institutionalized), have become set in their ways or have learned only from their managers who spent a career in government. They don’t know any different ways. For many of them, their only knowledge from the outside is through salespeople.
It is our responsibility as employees to inform them about different ways to do things, perhaps better and more cost effective ways. If they don’t listen, and often they won’t, for various reasons, then at least you know you tried.
Most managers will be glad you spoke out. They want to hear different opinions. In the end, it falls on them though. They have to decide if your opinions on something are better than the “safe” choice. And many times they’ll still settle for the “safe” choice even if its more costly.