You realize that either way, you pay their employee's salaries. The cost is passed on to you wrapped up in the cost of the food, product, or service provided. Places that expect tipping are telling you up front they didn't include that in their costs so that you can provide what you believe was fair pay for the service provided separately. If you abuse that and demand service and provide no pay for the service (no matter what), you're the one making yourself look bad.