And I am not completely against the "space aliens" explanation for them, but I do think it's not the most likely explanation. Even something from another dimension or something demonic or otherwise "supernatural" seems more likely to me.

Unless they really are some sort of frat boys and those aliens have figured out a way to travel long distances cheaply and fast enough that even their students can do it in their cheap old junkers just for some Saturday night fun.

Okay, if it's that it may actually be rather more terrifying than any alien invasion ran by their military...