Yeah, that crosses my mind too. They don’t really address the point that most people can’t tell their ass from their elbow, though. I mean, we’re talking about crazies anyway, right? 
While I’d like to believe that a lot of sightings are attributable to stuff like balloons, plastic bags, frisbees, toys, or fireworks, none of those things have the fast and linear flight paths or altitude exhibited by the most controversial sightings, which is why I’m sure the most controversial sightings are experimental aircraft operating at a level well beyond the rules of standard airspace regulations. UFO photos are always too blurry to make out any detail (either because they’re hoaxes or being mistaken for something else), but the interesting parts of stories involving multiple eyewitnesses are the descriptions of the movement of the unknown objects. They don’t move like frisbees, balloons, or planes. They change direction, move at ridiculous speeds, disappear, reappear, etc.
I saw something in the sky once, in the middle of the night, that didn’t move at all. Thought it was the moon at first, but I quickly realized that: 1) the moon was on the other side of the sky, 2) it was too small to be the moon, 3) it was too big to be a star or planet, 4) it was much brighter than anything else in the sky, 5) I’d never seen anything like it before, and 6) it vanished behind cloud cover after a few minutes. Was it controlled by aliens? Don’t think so. Was it controlled by people? Could’ve been. Was it a planet like you see in this photo? If it was, it would have to have been way off its orbit and only a few hundred thousand miles away because it was several times bigger than either of the planets in that photo. Was it a geosynchronous satellite in an unusually low orbit? It looked like a great big glowing pearl in the sky. If I could compare it to anything, it was like a stadium flood light, but it was many hundreds of feet in the air. I might also add that I don’t live in a remote area, so I don’t really get to appreciate the beauty of cosmos with any real clarity, so if this was an astral phenomena, I have no idea what it may have been.
I know for certain though that what I saw was no cloud, paper bag, frisbee, firework, spotlight, or airplane. Kinda like the pilots in the story.