As someone who has worked in the service industry, and now frequently dine out, I vehemently dissagree that the prospect of a larger tip does not motivate service industry staff.

No matter - do away with tips. I will continue to tip voluntarily and I garuntee I will recieve superior service from appreciative staff.

They don't know how much you're tipping in the beginning so you're almost never going to get "superior" service on the first go. Also highly dependent on context. Moving some food around doesn't have a big spectrum of quality.

Tipping voluntarily as you say is just building up a relationship with money. Neither unique nor special, but it's not exactly what's being discussed here.