Deuteronomy 7: 8:

Deut 7: 8 It is because Yahweh loves you and keeps the oath that he made to your fathers, who brought you out of Egypt with a mighty hand and rescued you from the house of bondage, from the hand of Pharaoh, king of Egypt.

God is the owner of love. When he freed the people of Israel from slavery in Egypt, he made it clear that he did it because he wanted to free them, out of love. Although the town as such, did not deserve it, freed it and nothing else.