Waitresses are unhandered

I went to Spur at the Waterfront the food was great but I did not appreciate the underhandedness of the waitress, who brought a bill that showed a tax charge of 20% of my bill. I then I asked her if this was the tip and she said no, and I even added a tip on top of that. Thinking about now the prices on the menu are inclusive of vat so I have now actually ended up tipping her 30% that is just not right.