The  old man placed an order for one hamburger, French fries and a  drink. 
He unwrapped the plain  hamburger and carefully cut it in half, placing one half in front  of his wife.
He then carefully counted out the  French fries, dividing them into two piles and neatly placed one  pile in front of his wife. 
He  took a sip of the drink, his wife took a sip and then set the cup  down between them . As he began to eat his few bites of hamburger,  the people around them were looking over and whispering.  
Obviously they were thinking, 'That poor old couple  - all they can afford is one meal for the two of them.'
As the man began to eat his fries a  young man came to the table and politely offered to buy another  meal for the old couple. The old man said, they were just fine -  they were used to sharing everything.. 
People  closer to the table noticed the little old lady hadn't eaten a  bite. She sat there watching her husband eat and occasionally  taking turns sipping the drink. 
Again, the young man came over and  begged them to let him buy another meal for them. This time the  old woman said 'No, thank you, we are used to sharing  everything.'
Finally, as the old man finished and  was wiping his face neatly with the napkin, the young man again  came over to the little old lady who had yet to eat a single bite  of food and asked 'What is it you are waiting for?' 
She  answered
(Continue  below - This is great) 
'THE  TEETH."