Roman culture was brutal by our modern, Western standards. Animal sacrifice was common and accepted part of religion. The Romans even had an priest official -- the haruspex -- whose job was to examine the entrails of scarified animals for messages from the gods.

Crucifixion of rebellious slaves, enemies, criminals, etc., was common place.

Gladiatorial combat to the death and other blood sports were common.

You're right that the Romans did not perform human sacrifice (or very, very rarely sacrificed humans), but there doesn't seem to be any major moral drive to defeat Carthage. Carthage was an economic and military rival. They fought. It's the story of human history.

Even the article you linked says, regarding Carthaginian child sacrifice:

'Indeed, contemporary Greek and Roman writers tended to describe the practice as more of an eccentricity or historical oddity – they're not actually very critical.

'We should not imagine that ancient people thought like us and were horrified by the same things.'