Saucy Asians

I simply don't get it. I was half listening to the TV and suddenly a lean cuisine ad got my attention. They were advertising a new product that featured an "Asian-style" sauce. This is one of my pet peeves. With only India and China combined, you've got about the third of the population. Does it really make sense to group all of Asia into catch-all category. Do Asians all have a similar sauce? Here's a blurb from their Hunan Stir Fry Beef:

Tender beef steak and whole grain rice with broccoli,red peppers and edamame in an asian-style sauce

Apart from wanting to call Chinese-style sauce because Hunan is a province in China, why throw in a Japanese word like edamame?

We don't often see advertising for lasagnia with an "European-style" sauce. Why should a dish from Hunan have Asian-style sauce?