Yes, they are victims of Hamas, but do they see it that way? I'm just speculating here, but consider:
How many degrees of separation are there between the typical Gazan and a Hamas terrorist? I'm guessing that many have fathers, brothers, husbands and sons in Hamas or know and are sympathetic to such people. How can these people not know where some of the terrorists are hiding? Or where some of the tunnels are. They likely know where some of the hostages are or have some information. If so, they are protecting Hamas from Israel. Not that Hamas is, but they don't see anybody else defending them, and Hamas is family, or a degree or two of separation removed - a cousin's husband or maybe a neighbor's son they watched grow up.
And if this is the mood there, then those who might want to cooperate with the Israelis do so at risk.