It could be an honest mistake, but it is also symptomatic of tipping culture today.
You do not have to be super observant to see that it seems like more goods and services than ever seem to require a tip, and many are demanding ever-increasing amounts of money. While there remain a few professions where tipping is a necessity so that workers can make a living, it has to be said that there are still plenty of scenarios where leaving a tip does not need to be a demand. It can be a nice thing to do to brighten someone's day, but it isn't something that should be made into an expectation.
Any controversy surrounding a refusal to tip is understandable. There are plenty of situations where that is always going to be bad practice. However, businesses have slowly co-opted this taboo and tried to use it in ways that it should not be used. It is only natural to find that quite annoying.
Many people have worked tirelessly to normalize turning the iPad back around after pressing 'no tip', but the demand for a little extra cash on the side continues unabated. Life is expensive enough without an unofficial tax on half the things that we buy, so why should it be something that we have to deal with? It would be better if companies just paid people more, regardless of whether their wages meet the minimum legal threshold or not. The customer is already paying a significant price.