In Cecil’s column about Romans and vomiting, he noted that Roman vomitaria were actually theater exits, not special vomiting-rooms in Roman homes. However, he also showed evidence that, all the same, the Romans weren’t shy about vomiting during or after dinner.
However, this article gives a fair bit of scholarly analysis to show that both assertions are, well, more than a little suspect.
Disclaimer: I am personally acquainted with the new article’s author.