Re: thus freeing up staff to focus on customer service
It won't free up anyone to be sacked, as anyone who has ever worked in or owned a restaurant can tell you.
You still need someone to check that the plates are correct to each order and each table. That's usually done by the server, or a kitchen 'expediter'. The cooks won't do that, they're on the wrong side of the line and if they screwed up the order having them check the order isn't very helpful.
Unless you expect the customers to take the plates off the robot themselves the server will still need to do that, and the inevitable asking for something else like BBQ sauce, black pepper or whatever will still require a server.
Carrying plates to the tables is a very small part of a server's workload, and having these things trundling along below your eyeline is probably going to be more of an annoyance to them than a help. And what happens when a customer decides to go to the bathroom and slides his seat back without looking and knocks a few plates off the robot or tips it over entirely?
This is just a "hey look at us and how futuristic we are" thing for restaurants to get. Just another theme like a rain forest or rock concert. It will COST them money to have it, and won't save any labor expense.
The bit about it being useful for bringing items to the delivery driver is another fantasy. Someone will have needed to box up and bag the order, and trust the delivery driver to grab the right ones and leave alone something that smells good when he's hungry (yeah he'll be on CCTV taking something he shouldn't but he'll claim it was a simple accident as he was supposed to pick up that Big Kahuna Burger at his next stop)