That's the way to hand-grease tapered rollers. Done correctly, it forces fresh grease in and old dark grease out along with contaminates, water or whatnot.
If you're using Delrin or poly a-arm bushings and are using zerks drilled in to keep them from squeaking, some try hand-cutting a long spiral groove like rifling in a pistol barrel on the inside so the grease from a zerk spreads along the whole bore of the bushing.