Lightfoot never recorded it with "pavement" but he definitely sang it that way for a short time in the 60s. There is at least one live recording that definitely has "pavement" and "never grows". It's one of 4 GL songs on a strange MP3 compilation of "country, blues and western classics":
www.gordonlightfoot.com/LiveLightfootCutsfromthe1960s.shtml
I love that version of the lyrics!