Bureaucratic zeal, probably (and a 9/11 scare?). Should you have been able
to answer them in Italian, they probably woulf have backed off. It's second
nature to them.

JL

They do the same thing at the White House in Washington...

At the ruins of the Greek temples at Paestum, a few kilometers south of
Salerno, the same thing happened to me.  I speak Italian and asked the
reason for this as photography was permitted and that I was using a
tripod with rubber feet rather than spikes which could damage the
ground.  The park employee became more agitated.  I later learned that
if one is using a tripod, one is presumed a professional and that the
photos would be competition for the guidebooks, postcard, and other
local photographic products.

The occasion I mention here was in 1999, so 911 hysteria wasn't a factor.

You have to get permission beforehand by paying a fee with some city
officials, as I recall.

There are a number of heavy pedestrian ways that are hard on tri-pods
on principal around the world.  You can catch grief in Manhattan!  If
you were lucky enough to visit Rome in January or February you can't
imagine the crowds on the Via dei Fori Imperiali or St Peter's on a
Saturday or Sunday in August or on a Tuesday in May for that matter.
You might think about a monopod for those kinds of situations, pass it
off as a walking aide.

There are a number of heavy pedestrian ways that are hard on tri-pods
on principal around the world.  You can catch grief in Manhattan!  If
you were lucky enough to visit Rome in January or February you can't
imagine the crowds on the Via dei Fori Imperiali or St Peter's on a
Saturday or Sunday in August or on a Tuesday in May for that matter.
You might think about a monopod for those kinds of situations, pass it
off as a walking aide.