Examples of Segmentation in Email Marketing

Call me whatever you want, say I'm wrong, I don't care, but I hate kinds of Email Marketing, no matter what, because everything comes with a catch.

Would I like a ticket with 50% off from Brazil to NY? OFF COURSE I WOULD! But I know that if you had to send a mass message about that, it certainly has a catch, so I won't even bother looking at it.