Different approach in the UK, especially in Restaurants etc.
The commission is actually built into your bill. What would you prefer in this instance?
The option to tip based on your service, giving more if you feel it deserves it or just to have a fixed percentage deducted from your wallet by default.
Other than that, exclusively looking at the catering trade, I understand that US waiter/waitresses survive on tips, while in comparison the UK equivalents earn enough to not worry about it.
I don't agree with tipping because of public perception or the position of the person expecting a tip.
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