Interesting to read the continual responses to my original post.
In response to Brain, the commercial wasn't advertising a product, it was advertising the Supermarket, and so in light of what you said, it shouldn't have been directed at a "majority" race. The supermarket would have been more appealing if the original brief was adhered to and a variety of "ethnic" people were seen, and as a result, would have increased their business!
Secondly, once again we really need to move on from this misguided idea that being non white in the business is a major plus and advantageous, with regards to competition.
Statistically, you are at an advantage of being seen by casting directors, experiencing more castings, and ultimately landing a casting, as a white actor, due to the sheer number of "caucasian" castings, despite there being more white actors on the circuit, than compared to a non white or racially mixed casting.
I was at a recent "last minute casting", race specific, and despite the casting being last minute, the casting director was still inundated with responses, in that, not only was the casting suite packed throughout the day, but also many submissions had to be rejected due to the sheer number.
In addition, the actors had to be bilingual, yet the numbers were still full!
I think, through no fault of their own, some caucasian actors have not experienced non white castings and therefore are not aware that it's just as competitive, or even more so.