Actually, the hashemite tribes were wandering ALL OVER THE MIDEAST for hundreds of years. So why pick this particular sliver of land and demand they be given it? Why not "give" them Jordan? Lebanon?
The only point Patrick actually answered with a real answer (trying reading the questions over again, Patrick) was the old Hashemite Tribes myth of Palestinian origin. A fairly neutral study was done (I believe it was three Israeli scholars, two of whom were Jewish) which found that only about one in five Palestinians fit the profile of being Hashemite. I guess that means the Israelis can ignore the historical claims of about 1.5 million Palestinians (including refugees). Still leaves 6 million people that your pathetic re-writing of history doesn't cover.
We'll just have to use our imagination as to where this study is and who wrote it.

Although the vast majority of "palestinians" are hashemite, sure, some other ethnicity is probably mixed in, but how does that change anything? The fact remains that "palestine" never existed as a state, and there is no such ethnicity as "palestinian"; the former is simply a colonial name for a territory, used by various conquerors of the region, and the latter is only a political term of art used to brainwash the uninformed and simpleminded.