Sorry Cecil, but I just read your 2002 post that vomitoriums did not exist in Ancient Rome. There may be a lot of things that you would not prefer that at least some Romans did, vomitoriums are definitely one of them.
I’ve actually seen a vomitorium in Nero’s Golden Palace. In 1989, I was on a summer archaeology program and in Italy for 1/3 of the trip. Nero’s was being excavated, it is very well preserved as it is under Trajan’s bath and was basically packed with rubble, sealed and had a bath built on top of it to erase the memory of Nero from Rome (not terribly effective in my opinion). We were allowed in during the excavation.
There is an “orgy room” which was basically a large reclinium or eating room with waterfalls that dropped down one wall, ran under the floor to turn a massive, marble lazy-susan-type table (so guests didn’t have to pass anything). There were anti-chambers with lots of options for guests. “Any manner of man, woman or beast” is a quote I recall. The vomitoriums were where the water ran out, it was a place a person could go to vomit if they wanted to continue feasting and were full or if they had too much to drink.
I don’t believe most Romans had vomitoriums in their homes, but Nero certainly had at least one off his Golden Palace in Rome. They did indeed exist.