I am not a fan of tipping. The history behind tipping is bribery. While it used to be optional and that you only had to tip for exceptional service, nowadays a tip is expect, even if the service is mediocre. 15-20% seems the norm and when you add that on top of taxes and the bill, things can get pricey.
#2 Sales Tax
Where I live tax is included in the bill, so there are no surprises when you go to check out. Although it varies state to state (some states don't have sales tax and some have local taxes on top of sales taxes), the average in 2015 was 5.45%. However, sales taxes and tipping can quickly increase how much you'll pay for things.
#3 Friendly People
I live in a very hierarchical society, where titles and bowing are the norm. While sales clerks may greet you as you enter a store, no one would think to greet you on the street or say hello unless they knew you. Since I'm not used to random people I pass saying hi, sometimes I get accused of being rude and cold back home.
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