the zombie apocalypse starts when they all run out of space...,

NYTimes | The world’s cities are running out of space to bury their dead. After all, apartment dwellers can’t bury relatives in the front yard. 

While traditions like All Souls’ Day, All Saints’ Day, the Day of the Dead and Samhain honor the dead this week, we ask a question for the living: Where will our bodies go?

(actually a rather widespread concern judging from this assortment of youtube videos )