But it seems wrong!

In accordance with suzerain treaties, no other god (read: ruler) was to be recognized in Yahweh’s territory. The significance of this is that the pantheon/divine assembly concept carried with it the idea of distribution of power among many divine beings. The first commandment becomes a simple statement that Yahweh’s power—at least within the boundaries of Israel—is absolute. He is not one of many who share in the distribution of divine authority. It is understandable that the Israelites would struggle with this concept. First of all, it removes Yahweh from the community of the gods. In the ancient world people found their identity in their place in their community. They assumed the gods did the same. To separate Yahweh from such a community identity would have been a confusing concept. Autonomy and independence were not valued in ancient society, and to ascribe these qualities to their God would have seemed impious.—Walton and Walton, The Lost World of the Torah, 237