brand name when govt insurnance pays?

Correct me if I am wrong but isnt this wasteful?:

A doctor prescribes a brand name drug when the generic is availalble. The patient pays a minimal amount because medicare and a military insurance pays the rest. The govt, aka tax payers are then footing the bill for an overly expensive drug. Isnt that wastful?

And how do you react as a caregiver? Is it appropriate to point this out? Can we say something like: Maybe you could ask your doctor if a generic is equivalent. Its so tempting-helping to cut waste in a very wasteful healthcare system. But is it our place, is it appropriate?

If all you see is the small price you pay its easy not to want to cut costs and ask for the cheaper brand.