Why did Carthage reject Rome's demand to move its population inland?

Carthage rejected Rome's demand to relocate its population to an inland site because the city’s economy was fundamentally driven by commerce by sea.12

Moving at least 10 miles (16 km) away from the coast would have effectively debarred the city from the maritime trade that sustained its prosperity and material resources. Because this demand would have destroyed their economic foundation, the Carthaginians viewed the terms as unacceptable and chose to resist the Roman siege instead.123