Does a plate worth $20 really take twice as much effort to serve than a plate worth $10?
Quite often, yes. A $20 plate is more likely to include salad/soup, bread, things of that nature, which does require more effort than bringing a sandwich with fries and nothing extra.
If a plate is worth $20, but the restaurant has a 50% off deal so it only costs $10, does the server deserve less for serving the same exact plate?
No. Tipping is based off of the total of the check before discounts.
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