I had been on only one cruise in my life: a hulking 4,252-person Royal Caribbean vessel that featured an ice-skating rink, a mini-golf course, a casino and a Johnny Rockets. David Foster Wallace’s famous essay on the perils of being pampered at sea rang true: Between the all-you-can-eat food, bad drinks and being compelled to participate in “Y.M.C.A.” more times than I care to admit, I was ready to never set foot on a cruise ship again.

Two things changed my mind, and led me to book a cabin on a seven-nighter to the Dominican Republic on Fathom, one of 10 Carnival brands. The first was the price: $249 plus taxes and fees. Even more shocking was that, after I had booked, the price dropped to $199 for an interior cabin.

The second reason for booking was that the cruise was not your typical party boat — Fathom bills itself as a “social impact” cruise company, organizing on-the-ground projects with local nongovernmental organizations and encouraging passengers to take part in activities like teaching English in schools, sorting cacao beans at a cooperative, or helping to install concrete floors.

This kind of “voluntourism” has become a legitimate travel niche: relatively well-off people popping over for a week or two to volunteer in a country in need of economic assistance. It was only a matter of time before the idea spread to cruise companies: Crystal Cruises offers onshore volunteer opportunities, as do certain Holland America and Royal Caribbean Cruises.

It’s raised important questions about the complicated nature of development work and whether these voluntourists actually cause more harm than good. Why, some argue, encourage untrained tourists to spend thousands of dollars to go on one of these trips when far more good could be accomplished using that money to, say, hire trained local workers?

“This is development ‘lite’ — we’re not claiming to be anything else,” said Gil Lang, impact guide manager for Fathom.

Lang, who spent nine years doing development work in South Africa, said he became disillusioned and frustrated with traditional development work. He believes that getting large corporations, like Carnival, involved ultimately helps more than it hurts.

“Whether the intentions are altruistic or not, it doesn’t matter,” he said; if even a tiny sliver of corporate profits can be funneled toward a good cause, it has a net positive effect.

But it seems that vacationers haven’t gotten the message. The Adonia, as our ship was nicknamed, which holds 777 passengers, appeared to be about half full when I sailed. I didn’t mind at all — in fact, I found it made for pleasant sailing and a relaxing, almost meditative experience. Fathom did not respond to a request for occupancy numbers for Adonia’s cruises, but recent events would indicate that my experience wasn’t unusual: While dates for the Dominican Republic cruise have been extended through 2017, Fathom canceled two planned cruises to the island nation, replacing them with a more popular cruise to Cuba.

And how was the cruise? With a few qualifications, I will say: very good. The Adonia, while lacking the amenities of some larger ships, had a few advantages, the most notable being a greater sense of community. I couldn’t help but strike up a conversation with someone after running into them multiple times in a day.

My lodgings, a balcony cabin on the bow of the ship, were excellent. The room was spacious, the bed comfy and the bathroom and amenities adequate. From my balcony I could turn around, look up and wave at the captain. Mostly, though, I just sat in one of the balcony chairs and gazed into the deep, stunning sapphire blue of the Caribbean. My cabin attendant was kind and kept my room in immaculate shape.

Food on the ship is free in three of four restaurants, including the Pacific, the large main dining room. Dinner was usually a game attempt at something fancy — venison loin with nashi pear, say, or panko-encrusted coconut shrimp. Drinks are not free, but also not overpriced: Cocktails are $8 to $10 and beers $5 to $6, to which a gratuity is automatically added.

When all was said and done, my final bill was $686.25 — a significant markup from my $249 purchase price, but still quite cheap for a seven-day cruise. That included a 50 percent single supplement, taxes and port fees, about $80 in gratuities, and another $80 or so for the outrageously expensive Wi-Fi.

I signed up for two activities: reforestation, in which volunteers plant trees and try to undo the effects of agricultural deforestation, and community education, in which groups of 20 to 25 volunteers go into homes in a local community and teach English. Disappointingly, reforestation was canceled because not enough people signed up.

I had better luck with my second assignment, teaching English in the small town of San Marcos Abajo. After a brief introduction in the sweltering heat, we were assigned to different houses. I met the girl I would tutor for roughly the next 90 minutes, a shy 11-year-old named Racieli. I was given a binder with a basic English curriculum. I wasn’t given much instruction or time to review it, but soon Racieli and I were reciting the alphabet and beginning to learn numbers.

Did it make a difference with a capital D? Probably not. But I think there was value in the experience, for both of us. Racieli had come out of her shell a bit by the end of our session and told me she really enjoyed getting to meet visitors, an experience that builds confidence and is not really measurable.

The passengers appreciated it, too.

“It was like the best of both worlds,” said Tia Taylor, a 22-year-old passenger from Columbus, Ohio, “vacationing and giving back to the community while having fun and meeting great people.”

Bruce Armbrust, an instructor at Lake Tahoe Community College, called Fathom “completely different” from any other cruise he’d been on, saying that the attitudes of the passengers really set it apart.

“There’s an element of wanting to help instead of just, ‘you’re here to serve me,’” he said.

If Fathom can successfully scale up these efforts, the effect might be more profound. Imagine having the 4,000-plus passengers on my first Royal Caribbean cruise each spend some time with a native family at one of the many ports of call, getting to know them and volunteering a few hours of manual labor, or trying to teach them a marketable skill. I would like to believe that would make a difference — still lowercase, perhaps, but worthwhile nonetheless.