dude, you are assuming that this being touted as be all it be system needing no additional layers of protection. what you are forgetting is the technology aspect of it which is proven highly effective which can be built upon. What you are also forgetting is that there are hot spots and not so hot spots like large cities that can also be targeted. So it takes additional batteries today , so what? the total amount of batteries needed for that country is stated to be 8 , they had only 3 or 4 this time around ready.
your fundamental argument is still flawed that just because it grabs 80% it is to be dismissed. in a war theater you have no clue what all assets need protecting. Bridges for example in remote areas or highways that could be the main artery for transportation of human and military assets. Things by it self that have high value but no population around it. The mobility of the iron dome making it all the more effective over.