I went through this in Luxembourg, one of the most boring cities I have ever been to in terms of something to do at night. Many of these places near the train station. I was desperate for something to do, and dropped in one of them. I thought the 15 euro drink was outrageous, but what the heck. Then the stunning Russian girl siddled up and asked for champagne. I had never encountered a bar like that before, so of course...here comes the bill for over 700 euros, with two large goons making sure I paid in full.
In truth, the girl was quite the conversationalist and I enjoyed chatting with her. But I had no idea what the price tag was on those little splits.