Relax, Niko's just taking a relaxing walk around Los Santos. You know, walking around IS still considered exercise. Niko and Roman probably moved to Los Santos looking to expand the cab company. Imagine if that DID happen in GTA 5 and Niko happened to bump into Brucie and Packie.
Niko’s original walking animation was one of the best. Gta Online’s default walking animation is too sassy and flamboyant, he likes he’s modeling for clothes on a runway. I never liked it.