francophile: You might have more experience than I do on the subject, but just my few Yen/Won:

I rarely invite new customers or contacts to buffet style eats, as it might lead to aforementioned unnecessary complications. Once the ice is broken and you are in a one-on-one or small familiar group setting, locals love nothing more than eating at luxury buffets without social pressure. As countries in this region are very family-orientated a Sunday brunch buffet invitation is a very good way of getting closer to people and their families.

What might lead to problems are buffets at company or official ceremonies and festivities as guests can feel inhibited because of peer pressure and enjoy the occasion less than they are supposed to.