We once overheard this from the next table at our first night in the dining room:-
Pax (without looking up or smiling) to waiter: 'Will you be serving caviar?'
Waiter: 'Yes Madam'
Pax: 'Good. I like caviar a lot'
Waiter: 'I'll make sure you get a double portion'
Pax: 'Make sure it's a triple portion'
Waiter: 'I will' (with a look on his face that she would get a triple portion - of something).
We didn't find out if she did. We moved table that night (for other reasons)