Hahaha I was wayyy off.
My parents ways book through a travel agency I believe. We have Triple A (AAA? Not sure how to write it) so I'm pretty sure we get discounts when booking through them. I know we always get some kind of on board credit to use from them, and some nice gifts in our stateroom when we get on (ex fresh fruit basket, cool rice Krispy treats). We always go on Disney Cruises but I'm pretty sure the same things are all included on most cruise lines. What's included in your price is your room, all your food (with some exceptions) access to on board plays/musicals/movies, night clubs, clubs for little kids, some activities (wine tastings and whatnot). You'll have to pay extra for wine & beer packages and other fruity drinks (alcoholic & smoothies) but you get unlimited access to sodas, water, ice tea (on Disney it's self serve on deck 10 or 12(?) depending on the ship lol). Food that's included is all your dinners, self serve ice cream by the pool, pretty much all the food on the decks by the pool. You can also order birthday cakes and stuff but you have to pay for that I believe. Some ships (Disney, I know of) have resteraunts that are adult only, which you have to make reservations for and are adult only.
As for your excursions, like snorkeling, you have I pay for all that. I think our triple A thing got us like some money to spend on it. Excursions can be expense (like swimming with the dolphins, usually like $140-$175 a person!) but a lot are reasonably priced. Some excursions I've done are swimming w/ stingrays (legit in the middle of the ocean), butterfly park tour thing, kayaking in the ocean, and rainforest tour. There are probs other, just can't think of any. You can book those online or when you get on board. It's best to book before hand online so you make sure you have a spot!
Not sure if I'm forgetting anything, but if you have any questions just ask. I've been on seven cruise (going again next summer!) so I'm definitely a seasoned cruiser lol
SORRY FOR THE NOVEL.