The extra space is to cushion the chips during transport so you don’t have a pile of broken chips and dust. Typically they are also filled with nitrogen as it is inert and keeps oxidation and moisture in the bag to a minimum.
I'd like to see one of these charts that measures the amount of air in bags now vs. in the 80s or 90s. I could have sworn we had fairly full bags of chips back then, withouth them being reduced to rubble like so many people say.
So most of them should be sold as nitrogen bags with a side order of sliced cooked potato (TBC), to avoid violation of sale of goods legislation in your country.