As UK Crew I often took Iceberg Lettuce home from the USA, ( don't ask, but the kids preferred them to the floppy leaf variety which was all we seemed to be able to buy in Darkest Dorset of that era ) then UK Customs announced that one needed some sort of agricultural certificate (name escapes me, Iso... something ) to import lettuce into the UK.
Walking back to the hotel in Seattle one morning, having completed the obligatory shopping commands at a Supermarket before returning to UK that night, I passed an office block entitled - USA Dept of Agriculture - so went inside and found a man in an office and asked if he could issue the necessary agricultural certificate to import lettuce to the UK ? He seemed to know what I was talking about, and agreed that he could, and proceeded to load a Remington typewriter with a sheaf of forms with interleaving carbon paper, then typed away for a bit, finally asking me my name, and then..... how many crates of lettuce will you be importing ? Just one, I replied. What ! he said, only one crate ? No, just one lettuce. After awhile he calmed down and asked WTF was I doing wasting his time ? Not my fault, I replied, the UK Customs demand a form for importing lettuce, and I'm taking one home for my kids tonight. Eventually he saw the funny side of it, and having taken so long, and more or less completed the form anyway, he rubber stamped and signed it and wished me the best of luck.
Arriving at Heathrow I declared Iceberg Lettuce on the crew Customs declaration, and an almost gleeful Customs Hofficer, foreseeing US Iceberg Lettuce available for his tea, promptly advised that I couldn't bring Iceberg Lettuce into the UK without the necessary agricultural certificate and he would have to confiscate it for destruction -at which I promptly gave him the cert. Collapse of stout party.
I never repeated the exercise, but sometimes it's fun to wind them up.