I wouldn't be worried. I've been to CM's Boma, CP, and H and V and in none of these did I observe anything that bad. The worst thing I noticed was someone scooping two items with the same spoon. And lots of things like the salt and Catsup happen in any place, Buffet or not. You have to understand threads on a message board are self selecting. So you won't get a truly random sample. You'd get the impression from the threads it's shere chaos every day at those places. For the most part when I went, people were well behavied.
On my trip, my grossout happened at Marrakesh which isn't a buffet at all.