Darija, the dialect spectrum including Moroccan Arabic and the dialects of Algeria and Tunisia, is not studied as often as the Egyptian and Levantine dialects, but it is becoming more common out of necessity. Many American study abroad programs are relying on Morocco as an island of stability in the Arab world. Unfortunately, this simply reinforces the notion that Darija is a secondary dialect that is not very useful. This is an unfair characterization. Darija and Morocco merit study on their own, not merely as a last resort.
So why choose to learn Darija? First, because all Arabic dialects draw on Modern Standard Arabic. Learning any dialect can strengthen your handle on MSA and the way languages change over time. If you are interested in linguistics, this will also be interesting to you.
Second, Morocco has played an interesting role in history: Al-Andalus (Arab Spain), Ibn Batuta (the Arab Marco Polo before Marco Polo), Ibn Rushd aka Averroës (introduced Aristotle to the West), Maimonides (famous medieval Jewish theologian and philosopher), first official recognition of U.S. independence, and the oldest university in the world.
Third, Morocco is a great place to visit attractions like Marrakech (#1 destination in the world), Casablanca, Tangier, Rabat, Fes, Agadir, Ouarzazate, Meknes, Volubilis, Tetouan, Asilah, Merzouga and 9 UNESCO World Heritage Cultural Sites. It is a very affordable place for food, travel and accommodations and you can see medieval architecture, painted medinas, mountains, deserts, film studios, green valleys and gorgeous beaches.