Affiliate Marketing Secrets

For instance, I live in the Pacific NW. If you go into a “smoke shop” to buy a pack of smokes, these shops are invariably owned by Koreans. Alternatively, when I was recently in the Palm Springs, CA area for a few weeks, I noticed the “smoke shops” were owned by Egyptians. I’m just using smoke shops as an example here, but as I get to know these Koreans in the smoke shops, they open up a little more. I have learned, in general, that these “smoke shops” make tremendous money. Now, why haven’t’ I seen an Average Joe Caucasian, or an Average Ned African-American, etc. go into the “smoke shop” business, if it’s so lucrative? (Which I -do- believe they are, spending my fair share of time in there.) Is their a “barrier of entry”, of some kind, that disallows other ethnic groups to gain a foothold in the “smoke shop” business? I consider myself a social scientist, but I never encountered the theories behind this phenomenon…whether it be Korean smokes shops, Vietnamese nail salons, or Indian owned hotel chains? (Plz don’t construe this as being racist or bigoted…I just am really curious!!!!) There has to be a term for this pattern, and a sociological theory. Thanks.