I've no idea why.
From Reuters:
A prediction that a huge earthquake would destroy Rome Wednesday prompted fear in some people and giggles of ridicule in others but officials assured the populace that the Eternal City would not be rubble by midnight.
The Internet-driven story of an impending tremor has dominated blogs, social networks and talk shows for days, so much so that authorities from the mayor down have issued statements saying earthquakes are impossible to predict.
That did not deter thousands of people from staying away from work and heading for the countryside or the parks.
According to some media reports, as many as 18 percent of city employees called in sick and Rome's notorious traffic did appear lighter than normal for a Wednesday in May....MORE
So much for that vaunted Roman productivity.