The speaker admires people with different vocations because they appear to have freedom and independence that the speaker lacks. The hawker can choose his own path and time, the gardener works without supervision and can get dirty or wet without being scolded, and the watchman walks the streets all night without ever going to bed. The speaker, bound by school schedules and parental instructions, sees these workers as having the liberty to make their own choices about where to go, what to do, and when to work or rest.