Many chains in the Service industry will have a particular customer service style for them to differentiate themselves among its competitors.
Maintaining this customer service style [level] is one of the most difficult thing to accomplish. Much of the success in delivering the customer service level a particular chain desire have to do with the nature of the staff and their training.
Large franchises like: McDonald's and Starbucks have international standards of conduct, which their disseminate to their satellite locations and franchisees. Although, in the case of McDonald's the execution of the customer service level is up to the management teams of the particular franchise. The latter is one of the deficiencies of McDonald's (McD's) compared to Starbucks.
At least in Hong Kong, McD's enthusiasm that existed in many of its young, teenage staff are lost when the Fall school season began. These enthusiastic staff are then replaced by the middle age laddies, who among other things do not speak English. The lack of English skill is a problem especially when many of the McD's are visited by local tourist while they need an escape from the local culinary delights.
Most importantly, these middle age staff behave as if they are working at a local Chinese fast food restaurant or a "Cha Tsan Tang" (aka. local eatery). The traits of these local restaurants are lack of smiles when serving, impoliteness and treating customers in a lower stature than themselves.
I strongly believe that to deliver a good customer service experience, one [the server] must conduct oneself just a level or more below the customer one is serving. When you examine the world's top customer service (CS) companies you will find numerous examples of this trait throughout their CS policies and other operational procedures.