Definitions vary
https://www.investopedia.com/terms/f/facilitating-payment.asp
"In general, a facilitating payment is made to smooth the progress of a service to which the payer is legally entitled, even without making such a payment. In some countries, these payments are considered normal, whereas in other countries, facilitating payments are prohibited by law and considered bribes."
In any event these transactions are legally restricted by some countries only when the payments are made to public officials not to stewards and bartenders on cruise ships.