In normal open, public buffets - yes of course, you're absolutely right.

But, on FT "dos" the organiser often gets a private room and gives a finite number to the establishment. So if 40 people are booked they plan and portion for 40 people. They don't keep adding food. They'll be meat for 40 people for example.

So those 10 thoughtful and considerate people at the front of the queue who take what Europeans would view as 4 or 6 portions know full well that they are eating other peoples food who will probably get none. It also means that if their are a few expensive luxury items on the table that are clearly protioned at one per person - then when they take six clearly then five other people aren't getting any.

That was my beef as they say!