Sicilian structures

Mid-week we get a request for a booking for a party of twenty, for a girl's birthday. She wants to spend a maximum of €60 - four bottles of prosecco. A bottle costs €16, so she wants a little discount, plus she will bring a cake which our waiter will slice and serve ... and of course, service is included - the plates and flute glasses and the dishwashing, and the laying out of tables for the twenty or so people. Although they will occupy most of the upstairs room, there is no rental fee for the space. Never mind that a table for two would generate €60 with much less effort. On the night itself, she saunters downstairs every so often, 25 years old with the ways of an 18 year old. She apologises that many of her friends haven't turned up and so she would like one less bottle ... this happens several times throughout the night, despite the fact that the waiter notes all twenty places are occupied at the table, with more standing. When she tries to renegue on bottle number two, he mentions this. In the end, the young lady pays a grand total of €35 for entertaining her large group of friends. The following night we have a booking for another party of 15 this time. They want prosecco and antipasti and fruit - plus the service and space, naturally, all included in €100. So €60 for the 4 botles of prosecco, leaves €40 for the fruit and antipasti - just over €2 per person. Errr, profit? And the man who made the booking asked for a discount on this ... As if he were doing us a favour. We decided that we need to ask for half of the total amount up front. I would have done this long ago, but my husband is afraid of offending customers. I think by now, though, that our reputation is well enough established. Otherwise, what is the point?