Rust has taken its toll on these fuel lines. In areas where chemicals are used to control snow and ice it's not uncommon to see fuel and brake lines rusted like you see here. Especially on trucks that plow the snow and spread salt. In most cases all the lines are replaced with new coated lines to help slow down the corrosion process. A key to prevent this from happening or at least slow it down, is to wash the under carriage through out the snow season. If the vehicle is purchased new have it undercoated.