Personally, I love them.
Colourful, different I really don't like the "Grey" buffet. Sandwiches, sausage rolls etc bit boring. Appreciate you can have Hors d'oeuvres style food at a cost as they are more time consuming to make. But all the Grazing table events I have attended have been enjoyable, and different. Various Cheeses, Meats, Breads, nuts, Vegetables, dips etc. Plus they don't have much left over. Or have I haven't notice the table being a mess, as the food is eaten.
I recently went to a Wake where, the Buffet was "Grey" I reckon 60%of the food went in the bin, it was dull and sad looking and I know wasn't cheap.
I have also done a big Ploughman's A Selection of Cold meats, Cheeses and Bread table for about 60 people that works too.