Apparently this is happening because:

“It’s because your flash drive uses the Unix Epoch to determine when it was created. The Unix Epoch is basically a number that increments every second since January 1st, 1970 at 00:00:00. The number is then converted to an actual date. But for some reason the time was set to 0. I’m guessing you’re on eastern standard time which sets you back 5 hours to display December 31, 1969 7:00 PM.”

Go figure.

[via Reddit]