My standpoint on this is the same as it is when someone suggests that ghosts could be involved with anything:
Can we prove that ghosts/aliens do not exist (on earth)? No, absolutely not.
Does that mean we should believe that they could exist? Hell no.
There have been thousands of "sightings" over the years. For a vast amount of those, an explanation could not be found. For every single one where we were able to analyse them, we found out that there was a logical explanation behind it. There have been thousands upon thousands of proven cases of it being natural or man-made phenomena, yet not a single case where we could actually provide sufficient evidence to even suggest the involvement of paranormal/extraterrestrial beings.
If I drop an apple 150 times, and it falls to the ground every single one of those, then I'm going to assume that it will happen again on attempt number 151.