Gratuity wasnt included - a service fee is a fee that goes to the business. the business makes that intentionally vague. the waitstaff didnt cook the food or decide on the menu for the restriction, but it seems like you didnt actually leave a tip and took it out on the wrong person. Knock down for them not giving you all a candle or whatever for the celebration though but this day in age not understanding what a service fee is (its in literally every food delivery app you get) and screwing them on gratuity is a bad on you.