jackz hits the nail on the head, I think.
It's definitely a case of what you like. The cruise offers you an "all-inclusive" adventure with many different ports, at none of which you'll spend more than a few hours.
An "all-inclusive" resort will offer you a lengthy pampered stay, with many entertainment/sporting options which you won't likely get whilst cruising!
They're really two wholly different lifestyles! If $$$$ is an issue, do as much research on-line as you can seeking out those inevitable costs that won't be a part of the "all-inclusive!"
Good traveling!
SWR