Based on a graphic scale for a map with a fractional scale of 1/50,000, why isn't "0" at the far left of the scales?

A scale layout with fine divisions to the left of zero and coarse ones to the right of zero allows an uncluttered easy-to-draw scale to accommodate high-resolution measurements. If zero is at the left, then the scale must have fine divisions over its entire length in order to perform the same task.