the sweet old couple

A little old couple walked into a fast food restaurant. The little old man walked up to the counter, ordered the food, paid, and took the tray back to the table where the little old lady sat. On the tray was a hamburger, a small bag of fries and a drink.
Carefully the old man cut the hamburger in two, and divided the fries into two neat piles. He sipped the drink and passed it to the little old lady, who took a sip and passed it back.

A young man on a nearby table had watched the old couple and felt sorry for them. He offered to buy them another meal, but the old man politely declined, saying that they were used to sharing everything.

The old man began to eat his food, but his wife sat still, not eating. The young continued to watch the couple. He still felt he should be offering to help.
As the little old man finished eating, the old lady had still not started on her food.
"Ma'am, why aren't you eating?" asked the young man sympathetically.
The old lady looked up and said politely, "I'm waiting for the teeth.."