Listen, we shouldn't hold it against anyone who support the palestinians, if we are honest we both would probably do the same if we weren't Israeli. Don't take it personally or as an attack on our values.
Rooting for the weak is an almost involuntary response in today world, we are all thought from a young age to stand up for the weak and the oppressed. Every heroic story we tell as people is always about the underdog defeating the strong, from David and Goliath to Robin hood and the Alamo, look at almost every movie ever made and you will see that.
I mean Israel was overwhelmingly supported by both the left and the right in the west until the late 80's or so, there wasn't even a question regarding the legitimacy or support of Israel beside the fringes of politics, ask yourself what changed? did Israel became more bloodthirsty or the palestinians suddenly abandoned armed resistance? Nope.
Two things happened, Israel solidified its position as a regional power so it was no longer to be viewed as the "weak" side in the Israeli-arab conflict, which leads to the second thing. Since the arab countries abandoned the Palestinians it was no longer viewed as a Israeli-Arab conflict which was the case before then, the whole conflict became lopsided with a clear strong/weak division of roles. I believe the arab countries did this on purpose since they knew they can't defeat Israel militarily but that's another story. The roles just suddenly flipped on us, while mentally we still view ourselves as the weak.
People who live half the world away, on a different planet to ours basically, have their own life, issues and cares to worry about, mostly. they aren't as involved or know the fine details of the Israeli-palestinians conflict as we do, they don't know Israelis or the Palestinians either, just projecting on them predetermined roles in a play . People don't have the time to form an opinion, it's just easier to be on the "good" side while there isn't really one, just a matter of how you frame the story.