Summary (...practicing expository writing):
Google's buses have been the focal point of much discussion, related to urban development, social equality, civic engagement, taxes, and business culture.
While the point remains contested, many critics believe that Google's buses represent a tech elite, that has "invaded" San Francisco with its high salaries. The critics say this influx is driving up the cost of real estate, and hurting the greater sense of equality in the Bay Area. Critics claim the buses are unfair because they use public infrastructure, like roads and bus stops, but are not public. Critics explain that companies exacerbate the issue by wiggling their way around corporate tax codes, to minimize tax paid to governments.
In contrast, the proponents of Google's buses espouse a general admiration (and at very least, an understanding) of Google's choice to use a private fleet to help its employees commute. The buses replace cars and their emissions, thereby decongesting roads; they enable longer work hours, making employees more productive; and they facilitate a social city-life for many of its young workers. Proponents recognize that an overhaul of public transportation in the Bay Area would indeed lead to greater public good, but concede that this is neither practical, nor Google's responsibility. Further, while not solving the whole problem, proponents claim the private bus fleet at least helps.
The debate over the merits of Google's private bus fleet even expand to a question of social equality, and whether a capitalist nation should expect equality. While it's clear that only a small fraction of Bay Area residents enjoy these perks, the notion of equality is not lost. By some opinions, the magic of American capitalism is not equality of possessions (or abilities), but equality of opportunity. In this sense, Google and its tech-giant siblings need not provide services for the entire community, but merely give each person a fair chance at being hired -- a fair chance at taking part in their employee benefits programs.
Finally, if deemed worthwhile, Google may choose to make more overt gestures of friendliness to the community to soften any ill-will from the public.