A robot bartender will cost lot more than a human one. Makes no economic sense
It depends.
Robots you pay for once. Humans you pay for continuously. Once you buy the robot then it doesn't get tired, it doesn't ask for a salary or sleep.
If you use a robot for one year it will likely be more expensive then one years salary for a bartender.
You will still need to pay for things like repairs and electricity for the robot. If you are paying the bartender only $2.13 per hour then these expenses would potentially exceed what you would pay the bartender.
A robot will also not be able to effectively upsell and encourage additional sales the same ways that a human can.
Have you ever seen a robot steal office supplies? Have you ever seen a robot take a smoke break without clocking out? Have you ever seen a robot watch youtube cat videos on the boss' dime.