Just because you have Caller ID, doesn't mean everyone does. Now most cell phones do, but are you certain you are calling a cell?
I ALWAYS answer the phone if I can get there before it goes to voicemail. That's the phone etiquette I was taught. I don't believe in ignoring when people call ~ they called for a reason, even if it is just to chat.
Maybe the rest of you have people calling you all the livelong day, but not everyone does. If you think you have telemarketers calling you and that's why you don't pick up, then consider getting a service like No Solicitation on your phone line. I have that on my line and telemarketers by law can't punch through.
As far as "out of area" or "unknown", I guess I don't understand why you are all afraid of these calls? Are you simply afraid that it is a telemarketer? If so, see solution above.
Some people have their phone line blocked, so it shows up as "Unknown" and they don't know how it got that way. My mom is a case in point. She's not sure what she did, but that's how it shows up on my cell. So when "Unknown" calls, it's always my mom.
OP, I'm with you in that people seem rude nowadays. One poster mentioned not wanting to be a slave to their phone. No one said you had to. I always ask when I call someone, "Is this a good time?" because I don't know if they are making dinner, getting ready to head out the door, etc. If they are busy, they tell me. It's not like I'll continue to talk their heads off if they are busy at the moment.
I especially hate when people use Caller ID to decide if they want to talk to you or not. When I got my first cell, I called my sister-in-law to tell her the number. She didn't answer. She called back later to say she didn't recognize the number on the Caller ID and didn't know who it was. That's why you answer the phone - to see who it is.
Sorry, I'm just tired of people not being polite in just answering their phone. Take steps to eliminate telemarketers if you've been stalked by them, but have a little common courtesy and pick up the phone when I call. And then if you decide you never want me to call again, just say it to me over the phone, instead of not returning phone calls, hoping to get the message across. Just hit me right between the eyes; I'm a big girl, I can handle it. Can you handle being an adult and saying that to me?
Off my soapbox now...can tell phone etiquette ticks me off?