However, Scenic Tours has argued that the weather conditions were beyond its control, and that the terms and conditions to which passengers signed up when they booked their tickets included an acknowledgement that the company could vary cruise itineraries "due to high or low water levels (or) flooding".
Documents filed by the company show it also denies that it "knew or should have known by about 3 May 2013 that the rising river levels would, or were likely to, substantially disrupt ... the enjoyment of passengers scheduled to embark upon river cruises".
In court on Tuesday, defence barrister Greg McNally SC admitted the "majority" of passengers were not given the option to cancel their trips.
Had the 13 tours been cancelled, he said, hundreds of passengers would have been "stranded in Europe".
The court heard that lead plaintiff David Moore and his wife had splashed out about $26,000 for what was to be a relaxing, once-in-a-lifetime trip.
Mr Moore, a Lake Macquarie high school science teacher, gave evidence on Tuesday that he was not broadly aware of the terms and conditions of his travel when he paid a $500 deposit for a "Jewels of Europe" cruise.
"You must have understood that there would be terms and conditions in relation to any contract you entered into with Scenic Tours?" Mr McNally asked him during cross-examination.
"Not at that time," Mr Moore replied.
"At the time of booking ... all we thought about was 'You beauty'."
The case continues.
- AAP