This is, of course, before Syria fell into war. But Jordan has been relatively stable even throughout the Arab Spring. Most Palestinians are not destitute and also have trades which could lead to them being productive members of those respective countries. So what gives? With Israel's expansion into the West Bank why wouldn't these neighboring countries welcome their Arab Brothers. I saw Arab Brothers because they often claim sympathy for the Palestinians under Israel's rule.
You have been misinformed. Depending on who's counting, there are between two and three million Palestinians in Jordan, or about half the population. It is the country that has been the most welcoming to Palestinians in the entire Middle East and, in fact, the world.