Somalis have pride and that prevents people from flaunting or showing off. It is a more valuable commodity than money. Jews also have plenty of that and that's why they don't flaunt too. Incredible self pride is contentious by itself. This people seek acknowledgment in something else, namely power. Somalis and Jews seek power not money, they only view money as a means not an end. And in their tastes they seek refined luxury not ostentatious. And refined luxury is usually silent not loud.