How do expatriates effect the local retail market in Gulf/UAE etc?

As per general available information, the retail sector provides over a fifth of GDP in tourist-oriented island economies, as well as in other major countries such as Brazil, Pakistan, Russia, and Spain.

UAE : Just like anywhere else expatriate population adds to the consumer base for retailers. Therefore, facilitating the growth of local retail markets. The expatriate population also help retailers diversify and innovate products according to various tastes and preferences. Further study and research for the Gulf and UAE may be required.

As this people break the margin level and sell the product but the retail market has the fixed margin as they need to follow the process of retail.