I usually do, but this past trip I definitely made an effort to limit the amount of food I ate and not worry about the price. FYI: we ate at three buffets: Tusker House, Beergarten, and Chef Mickey's for dinner, and one family- style - Ohana's - for breakfast. Instead of taking a scoop of whatever it was I wanted to try and ending up with a mound on my plate half-way through the line, I took only about two bites worth of whatever struck my fancy. This meant I returned to the table with what I would consider to be less than I would get from a regular sit-down meal, without putting something off until the second "run". Then, when I back for seconds, I made sure only to take what I really loved and only enough to bring the meal to the same level as a sit-down which meant that I probably could have used a soup bowl instead of a full plate,. Not only did I have room to enjoy desert and a beer (which I usually do not partake in because of "space" concerns), I managed to leave feeling good as opposed to feeling like the character in the Meaning of Life (re: no room for an after-dinner mint).
And, in the sense of full-disclosure, I usually gain between 5-10lbs after a typical trip. This time, however, I actually lost two pounds. So, while I am usually one of those worrying about getting their moneys worth, I definitely think my strategy this time around was better in the long run.