What about the 100 people who also owned homes within a few blocks of that apartment building and are also opposed to the change that it brings to the neighborhood? Zoning laws don't exist because of one loudmouth, they exist because solid majorities of the people who live in a given area like having them.

In your example, your side is outnumbered by the residents of a single apartment building.

This whole thread is kind of silly, in that high-density apartments aren't what's going to get built on SFZ blocks in cities and inner-ring suburbs; 3-flats are.