The phrase itself doesn’t matter, they are just listening for some indication of human speech at the start of the call.
If nothing is said, then the system believes that it is a machine doing the same thing.
Provided, of course, that their spam system doesn’t just starts playing a recorded message anyway.
Iirc, the higher water content keeps the alcohol from evaporating off as fast, keeping it in contact with the surface for a longer period of time.