Actual scarcity would not be beneficial to Hamas. They need food and, especially, fuel, too. They also need people under their rule not to be desperate enough to riot against their rule and demand surrender.
Hamas may be effectively unopposed because they've become good at deflecting local opposition. Put yourself in someone else's sandals. Why would anyone riot against Hamas, if they're mostly seeing their suffering as being at the hands of Israel/etc? Or, if they're even a bit more informed, too busy just trying to survive? And between the totalitarian regime directly in your face with a smattering of armed men vs. the everpresent threat of being bombed from above if you even
look like being an organised armed group (regardless of who you are arming against), what chance do you have?
Yes, Hamas is probably nurturing/shifting the blame as much as possible, twisting the mixed messages to their benefit ('the West' is against Gazans, hence the attacks, but 'the World' is supporting Gaza in its struggle, hence the aid, for example). That's just politics, as much as anything else. But, whatever your (or my) outsider feelings about who is primarily/mostly/totally to blame, the feelings of the grass roots and general population decree who is supported/opposed. Turkeys
can be persuaded to vote for Christmas, and it wouldn't necessarily be the turkeys' fault if they do.
This is not a perfectly logical world of perfectly critical constituents who all have perfect knowledge of who is helping and who is oppressing. And scarcity
can totally be beneficial to Hamas. They won't be the first to starve, but they do get first dibs on telling those who starve (in leiu of them) whose fault it is that this happens.
They won't actually say "we're shaving off the lions' share, leaving you with nothing", if they're doing that,
except maybe to encourage someone to join the pride who looks like they might want to
be a lion. (But as likely will be used as a sacrificial lamb, solving both manpower and rationing problems!)
PPE:
edit: this is @Strongpoint (see end 'PPE' for my slightly surprising response to Bumber!) ...the problem with that (the absolute shunning of Gazans) is that you're assuming that the whole of the Gazan population is a "Warrior Race", equally culpable and every man-jack (and woman-jill, and child-jojo) determined to fight, fight, fight as part of an genetically ingrained martial philosophy that goes against all 'civilised' reason.
Have you looked at polling from Gaza?
If you mean in terms of 'general support for Hamas's position', I've dealt with that (actually, just done it more explicitly, above, but you won't have read that until just now). Because you can't be somehow saying that polls reveal that Gazans are, from birth, Klingons/Tyranids/Magog-and-slash-or-Nietzscheans and irredemably martial in nature.