All the factors you mentioned are just the price of doing business. Just increase the menu prices to reflect the costs and if you can't stay competitive then do something else. Same for any business. Tips are a gratuity you give because you want to give a reward. It's not to subsidize a business expense.
I agree and said I did not charge any 15% to any one except parties of 8 or more due to my size which is an American practice.
But Its not America, and I just happened to be an American owner. Its a predominantly European based island doing this practice, and your opinion does not matter to the people who charge it.
Everyone has the right to not frequent any establishment they deem to be unfair to you. But if you like it , you'll go back.