Interesting.
A quick search in the bay area seems to confirm, at least to some extent, the article's findings.
I searched the east bay for Safeways. Rockridge, Piedmont, Montclair, Alameda (all better off areas): check, check, and check.
If you see the area south of downtown Oakland all the way down to almost San Leandro is completely devoid of all Safeways.
In my experience of driving through those areas, they are mostly served by discount stores like FoodMax, Food4less, or other ethnic stores.
No real point here other than I checked what the article said and it seems to jive with reality.