Recalling her waitress jobs of some 45 years back, my wife said the biggest tip differentials were cleavage driven. She was extremely good looking, but not especially busy, LOL.
She never mentioned pigtails...but styles change. She had beautiful strawberry blonde hair, but that didn’t seem to matter.
See, nowadays they got “water bras” so even the non-busty waitresses can get those “cleavage” bonus tips.