It's the scowling faces in the leaflet that do it for me. Actually has the effect of making the whole thing vaguely comical, which I hope was the intention...

To be fair, it's mostly common sense (OK, I didn't know about the bike-parking thing until I stumbled upon it by accident in a non-travel book). However, many do seem to leave their common sense for collection on return to their home airport. I believe World Duty Free offer this service at Heathrow.