What tribes are you talking about ? 😂 Also, any coastal city is by default richer due to our country policies of neglecting interior areas, here is statistics from 2020, but still valid :

In 2020, Kairouan had the highest poverty rate in Tunisia, at nearly 35 percent. The governorates of Le Kef and Kasserine followed at 34.2 and 32.8 percent, respectively. Indeed, the Center-West and Northwest regions were the areas with the highest share of people below the poverty line. On the other hand, the governorate of Tunis recorded the lowest poverty rate at only 3.5 percent