Single are you?

A guy walks into the supermarket and buys the following:
1 bar of soap
1 toothbrush
1 tube toothpaste
1 loaf of bread
1 pint of milk
1 single serving cereal
1 single serving frozen dinner

The girl at the checkout looks at him and says, "Single are you?"

He replies sarcastically, "How did you ever guess?"

She replies, "Because you're fucking ugly."