It depends. As I said, we've been to Hedonism in Jamaica, and it is as you said. It is indeed sexual, but most people there are couples over 50. It is expensive - roughly $250 a night in 2011 plus airfare, making it difficult for youngsters. You might get into some 3+ somes quite easily if you are a social person and hang out around and talk to people during daytime, but only if you're white. If you're black then it is much harder as you'd have to compete with local Jamaican dudes - the hotel lets them in as well just for that purpose, and they're typically young, well-groomed hustler types with a good game. This of course won't be relevant in Mexico or Argentina, but they may have some locals doing that as well.
Personally if you're going for pussy and not for the resort itself I'd rather stay in a regular large hotel; much cheaper and more opportunities.
Personally if you're going for pussy and not for the resort itself I'd rather stay in a regular large hotel; much cheaper and more opportunities.