Not just smaller cities, but also, as previously stated, big ones. A not very exhaustive list: Prague, Vienna, Budapest, Brussels, Zagreb, Rome, Milan, Naples, Amsterdam, Berlin, Oslo, Lisbon, Warsaw, Moscow, Belgrade, Barcelona, Stockholm, Zurich, Bern, Geneva, and the suburbs of Paris all have in common that they are all important, wealthy cities that certainly have the means to tunnel their systems if they were so inclined, and yet they have tram systems running through their city centres with exposed overhead wires. Did it ever occur to you that maybe they didn't do it because it's an insane waste of money and time?
There are so many more useful things that the money you would spend on burying a tram line could otherwise bring. If it is good enough for Rome, it sure as hell ought to be good enough for Brampton. Perhaps these people who have a conniption at the sight of surface transit and who see fit to be so generous with our tax dollars can get together and raise the money required to build the tunnel themselves.