One of the things I enjoyed about The High Cost of Free Parking was the way Shoup explains the practical effects of parking requirements. For example, requiring one parking space per X square feet is equivalent to setting a cap on building coverage.
Take Austin. For most retail, it requires one parking spot per 250 sf. According to Shoup, a parking space requires a minimum of 325 sf (and I've been told by some architects that the minimum is actually higher). Austin's parking requirement is thus equivalent to mandating 1.18 sf of asphalt for every one square foot of building. It ensures that building coverage will always be less than 50% of the lot. Much less when one counts front setbacks and a 25' rear, no-parking setback when single-family homes are close by. Although retail zoning districts theoretically allow a 1.0 floor-to-area ratio, the parking requirement ensures that the floor-to-area ratio will always be much less than that. And so we get buildings relegated to the rear of lots, segregated from sidewalks by a swath of parking.
Most ridiculous are the parking requirements for cocktail lounges. The ordinance requires one space per 100 sf for the first 2,500 sf, one space per 50 sf for the next 7,500, and one per 25 sf for anything over that. Hence, a 5,000 sf bar must be surrounded by nearly 25,000 sf of parking.
Another way of putting the city's parking requirement for cocktail lounges: "Sure, you build a bar, but only if you guarantee each patron that he can drive there for free."