Chopsticks

A couple was waiting for their food at a Chinese restaurant when an elderly waiter set chopsticks at their places.

The woman made a point of reaching into her purse and pulling out her own pair.

"As an environmentalist" she declared "I do not approve of destroying bamboo forests for throwaway utensils".

The old waiter inspected her chopsticks. "Very beautiful," he said politely.

Spoiler:

"Ivory".