Even more so are the noses of our 4 legged partners.
Heheh, I used to take an apple from the hotel to work for lunch every day when I was travelling on a job. Always carried it in the front pouch of my computer bag, with the power cable. Did this for a number of weeks.
Then I flew into Perth, where they control for incoming produce, even on domestic flights. I didn't have an apple in my computer bag, but a Beagle sat down next to it anyway. I explained to the handler, opened the bag, nothing there.
That dog gave me the dirtiest of looks...