Although it is always considered civil to treat service providers respectfully; but you should not be rude, particulary to a Waiter or a Waitress.

 Why? For this reason:

 A South Carolina, USA, county's deputies say a McDonald's employee spit in two customers' cups of iced tea after the drinks were returned because they weren't sweet enough. Authorities say 19-year-old Marvin Washington Jr. was arrested Wednesday and charged with malicious tampering with food. Greenville County investigators say surveillance video caught Washington leaning over the cups before he filled them Saturday at the Simpsonville restaurant. Authorities say the customers discovered phlegm when they removed the lids of the drinks to add more sugar because the iced tea still was not sweet enough.

 So next time you eat outside, treat the waiter/waitress with respect. This will ensure that your food remains non-contaminated. Try giving a Tip to waiter/waitress as well. The act not only makes then happy; but also makes you feel like a King.

 Tipping Rule is: 10 Percent of your Bill Amount. That's if your Bill amount is Rs 500; then leave Rs 50 as Tip.
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