I can hear you now. "Why don't you mind your own business?" (I'm also hearing you say, "Despite this angry open letter, I find you strangely attractive. Have you been working out?" But let's not get off topic here. Also, thank you, yes, mostly abs.) We can't mind our business. We used to hate the loud cell phone talker -- the man or woman barking into his cell phone in a closed space. If you were chatting away in a store or bus or train the only words that should have been audible were, "I can't really talk now," followed by rushed, quiet tones. And some people were polite about their conversations like that. But you can't be polite because you're projecting your voice into the mic, we're hearing both sides, and we see who you're looking at.
Trust me, we're not eavesdropping; you're creating a public spectacle. If you're FaceTiming in public, you should have the same expectation of privacy as a someone setting a baby seal on fire in the middle of a Walmart. Which is to say, zero. None. No privacy. So stop doing it. (Public FaceTiming or setting seals on fire, actually.) Try showing a little common courtesy to everyone around you instead of expecting the world to practice better ignoring skills. People who wear patchouli can't get mad at the rest of the world for having the ability to smell.