For the several reasons stated in the comments, this version is not a satisfactory replacement for a human bartender. In spite of the massive arms, it's still very slow and clunky in comparison to a human. But, it's a decent niche application for a robot that does work reasonably well, and the novelty aspect will probably draw customers for a while.
Developers: The serving robot should hold the cup 1/2 from the bottom using world view and staying level. Think of when we have a very full Solo cup. -- Robot and PLC programmer/archetect