>>63951609
On the contrary, they would be very cute logisticians, which makes up for their cost. And you can't deny them access to the military because that's discrimination, so your options are either let them get obliterated on the front line where they will get 360 noscoped by a hellfire to their gigantic cranium, or you let them carry tanks around and make the other logistics guys happy.

Also if you linearly scale up a girl to this (pic related) size, she would be capable of lifting like 300 metric tons, and her walking pace would be around 90km/h. You could replace a lot of very specialized heavy lifting machinery with someone like that, which might balance out the cost a little more, though she would probably still eat like 12 tons a day.
Imagine...
>Sergeant-sama, she's all patched up! Where do you want her staged?