I went to bistro k2 on Sunday night of May 29, 2016 at 645pm. When I went to pay my bill of $66.06 for only 2 people, I left a $4 tip. It is my opinion that the bill of 66.06 is already high enough for 2 sushi dinners. A $10 tip was too much in my opinion for a quick sushi dinner. A tip is at the customer's discretion. Has tipping become a tax? If so, why is that? The woman taking the payment then proceeded to tell me the tip was not enough and asked me if I had any more money to make up the difference. I explained to her the customer can tip at their discretion and I wouldn't be leaving any more money. I had already paid my bill in full plus some and they wanted me to stay and pay more money to them. I then proceeded to walk out but I turned around and asked to speak to a manager. I felt the woman taking the payment was rude to ask for more of a tip. I asked the manager for the $4 back that I left because I wasn't interested in tipping that night due to their attitude. I was then told by the manager and I quote "here's your $4 and please don't come back". I guarantee you I will never return to this restaurant.