As an American living in the UK over the last 19 years but who still has a fair few friends and family members working in the serving industry in the US, here is my take. American servers get an absurdly low basic wage, well below minimum wage, and it is expected the remainder will be made up with tips. When I moved from the US, the standard tip was 15% but it has slowly drifted up to 20%. A tip below 15% is seen as low, and would indicate either that you were unhappy with the service or, well, are a stingy person. Anything below 15% is effectively taking money from a server as they will still be taxed on a 15% tip. That's part of why the standard has moved up, so they get something additional. Disney suggests an 18% tip, which is well within the normal range. They state this will be charged for parties of 6 or more, so not paying that without good reason is actually like not paying for your dessert without good reason. I wouldn't expect to be able to adjust the cost of the food to the value I thought it represented unless it was truly awful and neither would I expect to be able to adjust the cost of the service when it is stated clearly before I ordered anything. Florida recently raised the minimum wage for tipped employees to $4.77 an hour. You can see that tips are necessary for any of those employees to make ends meet.