Exactly. The scam is that Cara WInsor Hehir believes she will be "brushing her teeth in champagne" and sitting down to dinner with somebody she mistakenly believes is a princess. That the hoi shall mix with the polloi is what Jarvis is selling; it also brings in gold diggers like Dana, Philip, pre-Amaury Nati, and Marie looking to score with wealthy guests. When Winsor Hehir discovers she is alone in the shittoo but for Kirsty and is expected to clean toilets, she finds she is homesick.
We shouldn't forget the time and effort PhiPhi spent to collect the most beautiful mismatched dinner service from various brocantes and antique stores for these special occasions. The rarest pieces came all the way from South Africa!