Crisp packets need to go into your rubbish bin as they can't be recycled. Although the inside of the packet is shiny and looks like foil, it's actually metallised plastic film, which can't be recycled yet.
Do the scrunch test
An easy way to find out if something is foil or metallised plastic film is to do the scrunch test. Scrunch the item - if it stays 'scrunched' it's foil and can be recycled. If it springs back it's probably metallised plastic film and therefore can't be recycled.