I tip my hairdresser $5. One reason you tip the person that cuts your hair is that they usually get 50% or less of the cost of your cut; usually less. That's how they're paid in most places. And it usually depends on what level of hairdresser they are, based by their employers on years since they were licensed. So lower level hairdressers will get 25%, 30%, 40% of the cost of the cut. They aren't getting paid by the hour.
The guy behind the Starbucks counter is not making below minimum wage to be subsidized by tips like a waitperson in many states. You work at a coffee shop counter and move three feet side to side getting the coffee. You don't get a tip. The cost of the cup of coffee is enough.
