"Israeli security sources believe that the man who blew himself up Tuesday night at a snooker club in the Israeli town of Rishon Le Zion was a member of the militant movement Hamas and came from Gaza."
LA Times, 5/10/2
The two Brits that came to Israel to blow themselves up also received their bombs in Gaza. The suicide bombings tend to follow particular acts of Israeli violence, usually assasinations. You're ignoring the possibility that they don't come from Gaza because they don't have to.