During our full time traveling years we traveled mostly on US numbered highways and state/rural roads. We used interstate highways in areas of the country that were sparsely populated where viewing the same scenery may last for hundreds of miles. There are large sections of highway US-1 from Key West, FL to Van Buren, ME.
US-1enters Maine at the town of Kittery. Shopping Malls there are like fancy strip malls elsewhere in the country. Here are pictures from Kittery.
Kittery, ME Mall - 1 Aug.jpg Kittery, ME Mall - 2 .jpg
Kittery, ME Mall - 3 .jpg Kittery, ME Mall - 4 .jpg