That's moving the goalpost. I posted this as a rebuttal to the (very popular) notion around here that the absurd yet sinister Israeli master plan is the death of everyone in Gaza through methodical strangulation and bombardment.

But to your point, I'll say what you probably already suspect is my answer, which is that Israel hits those targets when Hamas uses them or their immediate vicinities to store or launch rockets. Yesterday the UN discovered Hamas had hidden a cache of rockets in the basement of one of their schools. A few days ago I saw a report filed by a CBS correspondent from her hotel saying that a strike had come very close to hitting an adjacent hospital, near which she had witnessed militants firing rockets earlier.

Israel intends to attack Hamas, not collectively punish all Gazans. Consider that they had worked on reaching a peace agreement with Fatah in the West Bank that would've stopped settlement construction there (the only place in Palestine where the are settlements) and made permanent the borders, totally irrespective of what was going on in Gaza until the unity government and flare-up this year.

Unless your point is that all of the land going back 90 years belongs exclusively to the Palestinians, in which case you're not serious about peace.