In Mexico people try to trick you by asking something for something innocuous, like the time, and then ask you for money.
Also a supposedly common scam is to get personal info such as names and phone numbers in surveys and, later, to use this information to make fake kidnapping calls sound more plausible.
The upshot is that you learn to ignore people who try to get your attention. I don't think it would work too well here.
On that note, I'd imagine that "don't ask for ANY personal information except an email address, right at the end" is a pretty good rule for this sort of testing anywhere in the world. Good point!
Also a supposedly common scam is to get personal info such as names and phone numbers in surveys and, later, to use this information to make fake kidnapping calls sound more plausible.
The upshot is that you learn to ignore people who try to get your attention. I don't think it would work too well here.