It is harmful to the economy, is a benefit to only a few, takes tax dollars from the many, and could have been replaced by a high tech teleconference rooms installed in each country as a one time expense. If we need a G20 summit surely there is a better place to put it besides downtown in the largest financial center and the hub of the railway network. A billion dollars could build a new UN like building in Iqaluit to hold these events every year rather than a one time blow on security and bailing out the businesses being impacted.
G20 in downtown does bring media exposure but so did SARS. Harper has basically signed us up for the equivalent of SARS willingly.