Oh don't worry about being that guy xD The reason why they don't have headphones is one part forgetfulness, one part laziness, and another part 'I have gone this far without drawing it aghagahggh consistency....? Even if it's wrong....? Something something.'
At one point I literally woke myself up out of a deep sleep realizing they didn't have them on and then I was like 'maybe I will edit it when the book comesoutsssszzzzzzz.....'
Its a magical post apocalyptic helicopter.
New webcomi; MAGICAL APOCALYPTIC HELICOPTER!
Considering how many action movies never bother with headphones, it's easy to overlook.