If you notice and use some logics to analyse you will see something is not right about the presence of Chinese and Vietnamese in Laos..
1. The Chinese who come to Laos would do the same thing : Open a small shop to sell all kinds of Chinese-made products, they are located in almost every conor of Vientiane and provincials... everywhere there is a Chinese shop selling similar things.. and if you really look closer... how much money can they really sell? why the number keep increasing?
2. The Vietnamese are everywhere too- particularly in rural areas.. they would go around looking for old-stuffs to buy.
They come here not because they want to do any of these things.. because they want to expand move their population ..it's too crowded in thier countries.
I don't know what they want from us, but soon in the next 20 years... half of the population will be CHinese and Vietnamese :)