While eating my evening cereals (from a bowel) I pondered the following:

When it comes to packets…lets say crisp packets, manufactures always advertise the fact that there crisps come in a foil lined bag which helps keep the crisps fresh. How the hell does this work! From what I understand, crisps stay fresh when they are in an air tight container, and plastic crisp packets are air tight (even the foil lined ones are made of plastic mainly), due to the fact that plastic is oil is based. This is very odd