Cruise Lawns

I’ve never been on a cruise, so many this is normal. I was flipping through a Travel magazine and saw this ad for Celebrity X Cruises.

So, questions …
1) Is this a normal thing?
2) How often are there only 2 people on it? I imagine it usually looks like the open lawns on campus on the first warm day of spring.
3) Do people bring pets?
4) What is this X? It looks like they put the X as a placeholder for when they came up with something really good, then forgot to come up with anything good.

It also says the boat has the first Apple reseller at sea on board. Handy in case your iPad gets a grass stain.