"Most everything" is exactly that. Once you strip away that your meals in the main restaurants are included, as is entertainment, other than water and soft drinks, you pay for it on Oceania as an extra charge. It is not a bad thing, but a difference in product. (I think both Crystal and Seabourn are excellent products, but on Crystal you pay for "most everything" while on Seabourn your drinks and gratuities are included.)
More to your point, on Regent Seven Seas most everything is included, even tours, but the price is quite high especially if you don't take the tours or drink alcohol. So for some, like you, it is a bad value from the get-go. For others they think it is the best thing ever.
Each cruise line has a different model of what its guests prefer. My common. ts are merely to elicit the differences between the products; not to decide that there is a perfect product and X is it. They make vanilla and chocolate ice cream for the same reason: People have different tastes.
Azamara is trying to be a very inclusive product without being a luxury product. By comparing the different models used by three different cruise lines using the same ships people can better understand what each cruise line offers and then they can determine what fits best for them...individually.