Why do British restaurants call their automatically added service charges anything from "optional" to "discretionary"?
I've seen this happen in such a huge number of places I've dined at and it's a bit hilarious - "a 12.5% discretionary service fee has been added to your tab.". I don't mind and always tip 5-20% as I find that it's appreciated and I'm American so I came accustomed to it and enjoy doing it even more when it's not expected, but that's all besides the point of the bizarre and ironic widespread word choice. 
Best Answer
In addition to possibly being of some administrative benefit as user71659 has suggested, these service charges are also a way that restaurants use to confuse customers into paying more than they otherwise would. In the past, it was common and expected in the UK for restaurants to add a service charge to the bill for large parties (usually parties over 6). However, recently, some restaurants started adding "optional" service charges to tables of any size.
The restaurants hope that customers will not notice the extra charge, and might tip in addition to the charge. Contrary to expectation, the service charge may not fully go to the service staff. In some cases, the entire fee may just go back to the restaurant. This practice came under scrutiny last year, and there was some suggestion that it might be banned, but this hasn't gone anywhere yet.
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What does it mean when a restaurant adds a service charge?
A service charge is an amount that is added to your bill in a restaurant to pay for the work of the person who comes and serves you. Most restaurants add a 10 percent service charge to the bill. 'service charge' 'service charge'Can restaurants add service charge UK?
According to UK law, service charges added by the restaurant are entirely optional. If you aren't happy with the service or if you'd prefer to calculate your own tip, you can ask for it to be removed and for a new bill to be printed.How much of service charge is added to a restaurant bill in UK?
Visit Britain, the UK's tourist board, says a 10-15% tip for food service is "standard".Why did I get charged a service charge?
Companies typically charge a service fee for things that go beyond the scope of purchasing their goods and services or having a relationship with them. This includes things that require more work on the company's end or more individual interaction between the customer and company representatives.Why Do We Still Tip In Restaurants?
Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.
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