There IS another explanation.
The Town simply places nearly all of the sidewalks at the edges of their rights-of-way as near to the property lines as practicable, to create a visible 'claim' and minimize future grief:
In some cases, the roadway allowances are wider than others, because those corridors have been designated for possible multi-lane expansions at some point in the future.
If the extra lanes are added, then the grassy boulevards (and driveway 'skirts') are reduced to make room for them.
The BUILDERS, on the other hand, are motivated to cram as many McMansions as possible into every hectare to maximize profits. So they design really large homes on really small lots, and take advantage of the perception that the Town-owned land beyond the sidewalk is 'there for the taking' by the home-buyers for their inalienable use.
Its even worse on the OTHER side of the street where there is sometimes no sidewalk, so those home-buyers get even more blindsided when and if the Town decides to widen the road.
If you go back and look that that map I posted earlier, you can see this setup along Clark. There are homes on the north side built so close to their property edge (i.e. the sidewalk) that there is almost no room for ANY large vehicles on private property at all (unless of course, there was somehow some special purpose place designated within the home where a car could be located
)
Blame the greed of the builders, not the Town.