Except with cruise ships, morally righteous people are declaring this specific thing wrong and trying to keep people from being allowed to do this.

The Guardian claims that "At full power the Harmony of the Seas’ two 16-cylinder engines would each burn 1,377 US gallons an hour" https://www.theguardian.com/environment/2016/may/21/the-worl..., which would be 5.2 cubic meters per hour, or 125 cubic meters per day, so something between 100 and 125 tons. Other sources I've seen claim "up to 250 tons" (https://www.colorado.edu/mechanical/2016/07/25/how-much-fuel...). A ton of diesel-like fuel produces around 2.6 tons of CO2 (the O2 comes from the air).

So let's say 750 tons. Split across 5000 passengers, a 7-day cruise would be 750 / 5000 * 7 = roughly one ton of CO2 per passenger per cruise.

Myclimate estimates the total footprint of a 7-day cruise, standard double cabin on a >4000 passenger ship, one day in port, as 2.1 t (this presumably also covers food etc. so it's not surprising that it's higher). They also estimate just the flight (one passenger, round trip, economy class) of a trip from New York to Maui as 3 tons.