Recent work on cosmopolitanism has emphasized how globalization generates multifarious connections that situate migrants from underprivileged origins at the center of global cultural flows, making them emblematic of an emerging working-class cosmopolitanism. While this article supports the aim of reclaiming the concept from its habitual elitist location, it shows that the unglamorous cosmopolitanism of transnational labor is often viewed by non-migrants with resentment, suspicion, and misapprehension. This unflattering facet of cosmopolitanism counterintuitively shifts openness to the world towards a post-migratory uneasiness and estrangement at home. Reflecting on the experience of Sri Lankan Catholic return migrant workers from Italy, I suggest that these unlikely cosmopolitans—far from being celebrated for their tolerance and worldliness—are often regarded by the non-migrant community as ungrateful and indulgent sojourners. Cosmopolitanism amongst Sri Lankan Catholic migrant workers is marked by a detachment from certain national and local idiosyncrasies, but while this may be a praiseworthy stance in the intellectual realm, its consequences often weigh heavily on the shoulders of those who leave the homeland. Following Martha Nussbaum (2002), I propose that cosmopolitanism can often be "a lonely business."