Solomon doesn't ask for riches, but he gets them in spades (3:13). Part of the reason for this could be that all that rich stuff is an unmistakable signal that the Lord is the real deity up in here. The Queen of Sheba put it this way: "Blessed be the Lord your God, who has delighted in you and set you on the throne of Israel! Because the Lord loved Israel forever, he has made you king to execute justice and righteousness" (10:9). Lots of religious symbolism is hard to grasp, but when people see Solomon's treasures, they can't escape the conclusion that his god takes good care of his people.
But wait a minute, wait a minute, wait a minute: since when is God all about the rich stuff? Elijah's pretty righteous, and he never gets anything close to Solomon's bling. This doesn't seem to jive with "Blessed are the meek, for they will inherit the earth" (see Matthew 5:5), does it? Is this just one of those Hebrew Bible vs. New Testament things, or do you think God has a reason for making Solomon in particular a symbol of his divine riches? Maybe Solomon was just a product of his time?