Japan has the right idea.
Maria Shriver now has a compaign to guilt people into tipping hotel maids (more?).
If you're in the service industry, it's your job to be nice. That's what their employer (hopefully) pays them for.
If I have a good or bad experience, I exercise my discretion by choosing whether to go there again. If the employer notices a trend downwards in customers, it's their responsibility to assess what that is - hopefully their in touch enough with their business to identify if it's because of their employees service and 'apply pressure' if need be.
I guess ultimately it comes down to culture. I (and the large majority of the non-US world) isn't accustom to paying 10%+ extra for bad and rude service and it would be very hard for us to understand why that happens.
I'm done commenting here as long as this site remains this unfriendly to differing opinions.
And that's after years of participation and over 15,000 karma points. Something has changed, and it's not at all for the better.