$1 tip for a diet coke is obviously excessive. If the cost was $2, then even a 20% tip would be 40 cents. I think a .50 tip would be about right.
If a cocktail waitress served only 50 drinks per hour, and got $50, THEN SHE WOULD earn $2,000 per 40 hour week (in addition to her salary). This comes out to over $100,000 per year. How many firemen or teachers earn this kind of money? I'm convinced that casino tipping etiquette rules are written by casino employees.
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