Hi Comis
They sometimes buy a few whites perhaps for their occasional non asian clientelle. Really its all down to price Im afraid. I read the occasional post specifying "salad potatoes", red onions, Spanish onions etc and I just laugh. These guys put price first and quality second (or sometimes third!) They all use Dutch onions if they're cheaper than British - which they usually are. At the end of the season, if theres a shortage, they will buy Spanish. All depends on availability.
I was once told that if youve got some poor quality produce, the asian restaurants will buy it. If its really, really crap then the Chinese restaurants will buy it
This is all fact my friends.