One of the most interesting things about the Oktoberfest, from an economist’s point of view, is the form of the contractual relationship [the waitress] has with the owner/operator of the tent in which she works. She is employed just for the duration of the Oktoberfest, and has probably the most high-powered incentive contract you will find anywhere. She has no fixed wage, but receives 9 per cent of the revenue on the beer she … brings to the table, as well as tips of course. Thus she has the incentive to maximise sales revenue as well as give good service.
And also this:
The price of an Oktoberfest Mass, the litre mug of beer which is the standard unit of consumption, is regulated, and is set each year by a committee consisting of representatives of the tent operators and of the City Council. Its announcement is always followed by a storm of protest — the increases are usually above the rate of inflation. For waitresses, the crucial numbers are those after the decimal point. Apparently, customers almost always round up to the nearest Euro, so a price of €7.80 is bad news, €8.20 good. For a waitress serving around 1000 Mass per Oktoberfest, this would make a difference of about €600 in tips.