What if all the UFOs were criminals on the lam?

[besilarius]

http://esoterx.com/2015/07/15/six-tons-of-unmarked-uranium-a-rocket-and-visas-for-sirius-or-the-earthling-gets-it/

[bbmike]

Nah, even criminals would avoid us. We are all already doing hard time on planet Earth.  :P

[JasonPratt]

Case closed! Erased my foes,
chased away by the black suits, shades and clothes!

Mission completed, I mean it, we won't be defeated
I'm sayin' we did it even with weapons depleted.
Galaxy defenders, don't act like you don't remember,
takin' contenders and provin' they is only pretenders.

Ladies and gentlemen, boys and girls,
the Men in Black is back to protect the world!
When the enemy is here, the elite is here!
So have no fear, lemme, lemme see you just

NOD YA HEAD!

[JasonPratt]

A little more seriously, there's a colorful fringe religious theory to the effect that all the UFOs are criminals on the lam (i.e. demons).