It was the Taliban who blew up the huge Buddha statues, which were in wetern Afghanistan, Mike. The Allied armies damaged the Ziggurat at Ur in Iraq - one of the oldest sites of human settlement - in the 1991 Gulf War. The fabulous Mediaeval Souq in Aleppo was destroyed last year in the Syrian civil war and the amazing Roman ruins in Syria as rumoured to have been severely damaged or destroyed. Napoleon's soldiers smashed up the face of the Sphynx in Giza by using it for target practice. Goodness knows what WWI and WW2 destroyed in Europe, when entire cities were levelled. In the distant past, ancient cities and redundant defences were dismantled stone by stone and turned into new buildings, because it saved the labour of cutting stone. Henry VIII destroyed English monasteries and Oliver Cromwell ripped apart Royalist castles.
So time, wars and politics progressively erase the traces of humanity's past and leave very little that we can use to understand how our distant ancestors lived. If you think humanity's cultural heritage has value, then mining ancient monuments for roadstone is vandalism, if you think that cultural relics are just an obstacle to turning a profit then it doesn't matter.
In the end, the road probably has less potential value to the local economy than the pyramid did. Though, of course, the loss to the local community's potential earnins would be irrelevant to the contractor who profited from destroying it.