What is the company’s incentive to make the package bigger than it needs to be?
Shipping costs come two fold… Weight and number of pallets. Weight change is negligible here, but the amount of air they need to ship will increase. They are incentivized to reduce it to a minimum to save on shelf, storage, and distribution costs.
I don’t agree with the can example. Those are physically smaller and lack meaningful slack fill.
Your points stand for the first purchase. After that people will know the proportion of chip to air, and be annoyed by it. If they could do a bag smaller with minimal chip breakage and less air they would both succeed at getting more bags out per pallet and be lauded for not cheating people by selling air.
The slack fill is functional, and I don’t see much incentive to over do it.