It doesn't cost a lot to make the kind of rockets Fatah and Hamas launch at Israel by the scores, nor to dig tunnels into Israel from which to launch attacks, something that Hamas, most especially, tries with regularity. I admit that it does cost around $25,000 to pay off the family of a Palestinian suicide bomber, granting them a kind of pension that the Palestinian Authority and Hamas typically quickly pay not long after a Palestinian martyrs himself by killing an Israeli or two, at minimum, before departing this mortal coil so gloriously.
Still, a great deal of the foreign aid, totaling in the billions of US dollars, the Palestinians have gotten over the years has been lost to corruption, having gone into the pockets, first, of Yasser Arafat and his friends (his estate somehow accrued more than $1 billion by the time of his death, something his wife Suha tried mightily to conceal) and now Mahmoud Abbas (whose kunya terrorist name is Abu Mazen) and his confederates.
The local Arabs who've called themselves Palestinians, since around 1964, don't want peace with Israel. They could have had that, and at amazing terms, not long ago. What they want is the extermination of Israel. Until that dynamic changes there simply won't be some sort of "Middle East peace," which is also something even the Palestinians' long-time supporters among various Arab countries (including Jordan and Saudi Arabia along with Lebanon), have seemingly come to realize, they having their own more serious issues with the local hegemon, Iran. In Egypt, nobody wants to lose their food (gotten mostly with American aid in many cases) just because the Palestinians want Jerusalem. It's not that big a deal to them, especially when more pressing matters, such as being able to eat, having been engaging Egyptians' attention of late.
"Politics is just show business for ugly people."