I figured it out sitting in my apartment the other day.
Dust.
“Dust in homes, offices, and other human environments contains small amounts of plant pollen, human and animal hairs, textile fibers, paper fibers, minerals from outdoor soil, human skin cells, burnt meteorite particles, and many other materials which may be found in the local environment.”
We Humans shed constantly. Our domain is littered with hair and dead skin cells. It literally coats our surroundings. When we have pets, it includes their hair and dead cells as well.
Why would aliens want to wallow in our debris by visiting us? Disgusting!
I wish I could remember who wrote it, but there was a science fiction novel that involved a visit from aliens who were even goopier than we are.
The guys in the bell jars on The Simpsons, drooling and oozing all the time, are another example.
Hey, we love our dogs and cats. And we sweep up a lot. We love our horses…and do a lot of shoveling.
However, it is quite possible that “sufficiently advanced” civilizations have tossed biology to the side and have robot bodies. Cool! I can’t wait! (Just got over a nasty blister on my foot…)
Aliens do visit us. Now skeptics keep asking questions like:
[ul]
[li]Why don’t the aliens show themselves clearly?[/li][li]Why would the aliens only abduct a few people, while leaving the vast majority alone?[/li][li]Why would the aliens concentrate in some areas like parts of Nevada, while never being seen in other, more populated places?[/li][/ul]
All becomes clear when we realize that Earth is an alien nature preserve/wildlife refuge. Just like park rangers try to minimize contact between humans and wildlife, similarly alien ‘earth rangers’ try to minimize contact between aliens and humans. Only a few alien ‘poachers’ manage to evade the authorities and abduct a human.