Add it all up, and humanity's chances of surviving a zombie apocalypse would appear to rank a lot higher than, say, a catastrophic meteor strike. For two, thanks to the deluge of movies, books, and tv shows, people, broadly speaking, have a good idea of what tactics may work and what ones won't. For one, there are tons of weapons lying around we could pick up and use against brain-hungry automatons.
Out of all the black swan events, one that humanity is possibly best prepared for is the zombie apocalypse.