Are you sure it's tipping? How come the sales staff in some supermarkets in the US are nice, even when they don't work on commission and tips? Perhaps it's a c

Are you sure it's tipping? How come the sales staff in some supermarkets in the US are nice, even when they don't work on commission and tips? Perhaps it's a combination of many factors: tips, commission, weather, culture, religion and guns that makes Americans nice (For the record, I'm not religious)