The issue is: why are restaurants not paying their staff “proper” wages? Why are they the outlier, subsidised by customers?
If I eat at a restaurant, I already know I need to tip to make up the embarrassing gap between what the restaurant pays them and what a proper wage would be. Just raise your stupid prices to account for that and let me not do math after I eat.
But no, the Great Unwashed love a good illusion, so posting the actual price of a meal will drive them away. Adult society is full of toddlers.