n. A person who walks particularly slowly and aimlessly.
[Paco] Underhill doesn't suggest changes in consumer behavior. He's all-accepting of mall-world reality, right down to the slow walkers the industry parlance disdains as "meanderthals."
—Kimberly Marlowe Hartnett, “Dissecting our worship of consumerism,” The Seattle Times, February 08, 2004
Call them meanderthals.

They are slowpoke pedestrians who delay foot traffic on sidewalks and then, without warning, jaywalk, forcing vehicles to slow down or stop while they do their own thing crossing a street.

Cellphone-toting meanderthals are dangerous because they are oblivious to their surroundings. Baby-stroller-pushing meanderthals could wipe out the next generation. Meanderthals of any kind survive only because most drivers use their brakes.
—Jack Brubaker, “Meanderthals and freedestrians make driving in the city a challenge,” Lancaster New Era (Lancaster, PA), July 23, 2002
1984 (earliest)

Peripatetic male: Meanderthal man.
—Bob Willett, “Pepper…and Salt,” The Wall Street Journal, February 03, 1984
This pun is a nice blend of the words meander ("to walk slowly and aimlessly") and Neanderthal ("an extinct subspecies of human beings").