It's never been more expensive in the U. S. to fill up the tank and take one last summer trip over the Labor Day weekend. The average price of regular gas was $4. 14 a gallon heading into the holiday, nearly a dollar higher than last year and well above the Labor Day weekend record of $3. 82 from 2012, according to AAA motor club. Nicole Collins planned to head from Philadelphia to South Carolina to visit friends, but she said her family has spent most of the summer close to home and not their...