We have many Chinese/Asian buffets in South Jersey and they have improved greatly over the years. Most offer sushi prepared continuously and stir fry made to order. They also seem to keep the amount of food in the steam trays low so that it goes quickly and they replenish quickly. There is also someone standing by to keep things stirred and check quality. It's surprising really. I am not a big eater at all, not obese, don't eat snow crab or any shellfish or fish (allergic) and am not the normal buffet eater but I like the buffets because it allows me to taste a little bit of everything. My family is picky and I can't eat much so if I order an entire meal of something I could be eating it for days. How boring. Buffets also help when you have picky kids who take one bite and "hate" it leaving you to pay for an uneaten meal. My daughter has learned to eat many more foods at buffets.
Granted there are terrible places out there and they certainly aren't authentic Chinese food (who caress really it's American Chinese and I prefer that anyway). I hate to see the gluttony and the terrible waste and am very careful to take very small amounts and not more than I will eat. If I am too lazy to go back for more, I shouldn't be consuming the calories. One buffet in our area actually posts signs, watch you like a hawk at the buffet, and will comment on your plate asking if you plan on eating all of that. I have no idea how they remain in business.