Because Israelis are wonderfully concerned about each other (i.e. nosy), they have also developed super-strength defenses against each other's concern. Which means that if you are on the Israeli streets, you should act as if you are in the witness protection program and are being approached by Mafia goons.
I first realized this just a few weeks after we arrived. The great thing is that I was actually with an Israeli in a cell phone store at the time, and the person asking questions was actually a Pelefone employee--a Professional Authority to whom Americans would gush out their Social Security number, bank account tracking information, and birthdate of firstborn child without hesitation. However, with an Israeli involved, the conversation went like this:
Pelefone Employee: Where do you live?
Me: Well, if you're coming from the Haifa direction, turn right at...
Israeli: (to me) Let me handle this! (to Pelefone Employee) She lives around here.
Pelefone Employee: Where, in the Krayot?
Israeli: Somewhere around there.
Pelefone Employee: Which one? Kiryat Motzkin? Kiryat Bialik?
Israeli: Something like that.
Basically, Israelis disclose information on a strictly need-to-know basis... and others don't need to know. In fact, the Israeli only disclosed that I lived in the area because otherwise Pelefone might not have helped me. This is closely related to the concept of not being a fryer. If you assume that everyone else is trying to pull something or stick their nose into your business, you play your cards close.
Now, this backfires when you are not, in fact, trying to pull something. I have another friend whose checks list an address in Tiberias. Haifa-area stores refuse these checks because they assume she'd only travel so far from home (one hour) to pass bad checks.
Another example: delivery guys regularly try to give me packages that aren't mine. When I insist that I am not, for example, Miriam Lipshitz, they assume I'm lying. If I point out that the name on my door doesn't say Miriam Lipshitz, they locate similarities between the name on their package and mine ("Maya! It must be short for Miriam!") or propose that I must have recently changed my name to avoid paying bills. Finally, I demand to see the address on the package, which is inevitably for a different apartment or a different street. The delivery guys flee.
So if you want to be Israeli, give vague answers to personal questions (and that includes not writing your phone number on the receipt when you pay with a credit card, even though there's a spot for it). Assume that every person you meet is trying to steal your identity and spam your computer, and you'll be fine. :)
P.S. If you don't believe me, look at the Facebook accounts of your Israeli friends. How many of them allow "wall" posts? How many of them use their real names? Exactly.
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