1) The Internet killed this.
2) Originally, this was a favor to the guests.
3) They, people got greedy and lots of folks demanded it.
...
THINGS GOT REALLY BAD:
Several people complained loudly if it was too busy to get a diver for their special message. Even worse, at times, folks arrived late for their ADR and missed the diver. A few even screamed at the hostess that the diver should come back for them, as this ruined their whole vacation. ENOUGH WAS ENOUGH.