[adventured]

That assumes the robots won't be radically superior at balancing than humans are; they will be. It also assumes you can push one over to begin with; you won't easily be able to. They'll be able to withstand far more force against them than a human can before falling over, and they'll have a nearly perfectly calibrated response to achieve rapid re-balancing.

As to whether it's ideal (versus whether it'll work), that's a very good question. Perhaps if you can actually make it work very effectively, it's 1) maybe (?) cheaper than having three legs, 2) more agile than a tank tread style and 3) easily navigates in/around and uses human things.

Clearly in the future there will be a plethora of robotic war machine styles for different purposes, for the same reason we use different weapons for different purposes.