I think the rest of your stuff was answered by someone a bit wiser than yourself.
You're mixing up "wise" with "knowledgeable" and "ignorance" with "idiotic". Being wise or not is in the eye of the beholder. For example, a lot of people out there think that fortune cookies are very wise while some of us think they are just a bunch of nonsensical but bang-in-the-head obvious truths. It's like saying "you are a mammal... your kind give live young..."
Now you're in a place where they more than likely haven't seen the workings of modern society.
I know what you mean. I'm having the same trouble with you right now.
that smoke signal reference doesn't even fit into the conversation since smoke signals can be seen with the eye itself without any devise. The signals we're talking about can not be seen by the eye itself but need a device to bring it into our realm so that we may see and hear them.
They're almost the exact same concept, just on a different scale. Smoke signals work by manipulating certain aspects of the rising smoke to tell others from a distance. We can manipulate certain aspects of the EM waves to communicate at a distance.
You have this notion that just because something cannot be seen is nonphysical. This is the thinking of a child. That's how the game peackaboo-I-see-you works. The child covers her eyes. Since she cannot see you, she automatically assumes that you cannot see her. You're suppose to have grown out of that phase.
The physical world is composed of both the things that you can see and things that you cannot see. Just because the radio waves cannot be seen by the eye doesn't mean it is not physical. I think you're stuck in a time warp or something.
Think you could tell them that there are pictures, moving pictures all around right in front of them or theres music all around them without wiping out a device to collect the signal?