Yes, I have to chime in with agreement about Carnival.
Granted, I've only had one cruise - but it was on Carnival.
I did not successfully explore the entire ship (sad!) before the cruise was over... but, that said, I never even SAW a specialty restaurant that charged extra. All food I found anywhere on the ship was totally free. All the drinks are also free (except anything with alcohol in it, of course, and also the small assortment of stuff in cans and bottles they leave in your room - they charge you if you actually drink or otherwise remove any of it, so just set that stuff to the side out of your way at the beginning, perch a towel animal on top, and pretend it isn't there).
What really, really surprised me, actually, was that all this free food was really delicious. In all honesty, I was totally and completely expecting the food to be of "edible" quality - and not one iota better. I was very pleasantly surprised at this turn of events.
Pretty much the only thing Carnival did that I didn't appreciate was leaving that stuff I had no intention of touching in my room. It looked like a "sucker trap" for people who are too dumb to read the notice that you'll get charged if you drink this, and it certainly felt rude that they left what looked like a gift at first glance but would have charged me if I'd accepted said gift. Oh well; everything else was so stellar that I was willing to forgive and forget that little detail.
Carnival does it right - no sneaky extra charges; if they say something is included, then they mean it. For that, they have my respect, and they have won my loyalty.
(No, that doesn't mean I would never sail a different cruise line, but it does mean that I will return to Carnival, again and again - not because I want "a cruise" and Carnival happened to be convenient to my needs, but because I will seek out Carnival's offerings and choose from those.)