A desire by Arab states to maintain the visibility of the Palestinian refugee issue in international politics has long been noted as a reason why Arab states preferred to maintain a separate UN apparatus in the form of UNRWA rather than incorporate Palestinians into the new international refugee regime in 1950-1951...
Palestinians were not the first refugee group to be blocked from integration in host countries. ...What was new in the Palestinian case was that a new narrative discourse developed by which host states could better justify this limbo status.
This idea of a third party sponsor is important for understanding how Arab states have responded to the presence of refugees in their countries, beginning with the Palestinians in 1948. At the birth of the Palestinian refugee crisis, Arab states faced a political challenge. There was, and largely still is, a popular Arab consensus insistent on Palestinian return as the only acceptable solution to the refugee problem. Yet while Arab states have supported and often encouraged this sentiment among their peoples, Arab governments have lacked the power to force Israel to accept repatriation. Arab host states found themselves insisting that Palestinian refugees should go home even though they lacked the power to make this happen.
Shifting responsibility for the refugees to the UN defused this tension. It accommodated the practical reality of long term exile without surrendering in principle the insistence on the return as the only acceptable permanent solution.For this political strategy to work it would not have been adequate for Arab states to simply persuade the international community to share the resource burden of hosting the refugees via humanitarian or development aid. Arab states wanted the shift of responsibility for the refugees to the international community to be highly visible, what Jalal Husseini calls “the necessary public emphasis on UN involvement.” This symbolism was important enough that when UNRWA was established Arab states asked that “UN” be added to its name, instead of the original suggestion that it be called “Near East Relief and Works Agency (NERWA).”
...This UN responsibility thesis is fairly unique to the Palestinian case, but the general pattern of state-to-UN responsibility shift is the common foundation of refugee policy for both Palestinian and non-Palestinian refugees in Arab host states. ...UNRWA... set up registration, education, health and other social welfare systems separate from those operated by the host governments.
UNRWA remains central to Palestinain [sic] welfare throughout the region. As Nicholas Morris has written, “UNRWA has direct responsibilities broadly analogous to those of a government‟s health, education and social welfare authorities.”
A key lesson from the early days of UNRWA is that responsibility shift offers symbolic political benefits to host states, in addition to its utility in facilitating shifting of resource burdens. .... In addition to helping to defray the resource burdens of hosting refugees, state avoidance of responsibility helped to deal with political sensitivities. The fact that refugees in the Arab world typically come from other Arab League states poses a political problem for host governments that do not want to accuse fellow Arab states of persecution. It is politically expedient to leave this task to UNHCR, and to portray the refugees‟ presence as temporary, just as was done first with Palestinians.
...In general, the theory I am suggesting is that Arab governments are likely to acquiesce to the presence of refugees on their territory only so long as responsibility for their maintenance and ultimate departure from the country is visibly assigned to an international body or other third party
The Arabs have been using the UN to avoid their own responsibilities of supporting their brethren (Palestinian and other) for decades.