Grasswalker
(n) the one unfortunate individual who doesn't fit in a line formed across a sidewalk by a group of walk-and-talkers (usually females). The individual(s) mentally refuse to walk in front or behind of the rest of their pack, as this will inevitably exclude them from conversation, so they walk in line, but on the grass by the sidewalk; or in extreme cases, off the curb and in the street.
Any passing stranger could clearly pick her out as the loser of the group, as she always assumed the role of grasswalker in their strolls about town.