A Macy's employee told a customer that they didn't have what she was looking for and to try the Macy's with a larger African American clientele, except she didn't explain it quite so well, but neither did she explain quite too poorly.
The shopper wanted a size 16-18 formal dress for an event and found nothing but casual wear in her local Macy's woman's department (ah, "woman's" - what a shit euphemism). She was told that the demographics of the store showed that the fancier wear was needed mostly by smaller women - their petite section was huge. Local larger women, it seems, didn't go out to nice places or job interviews, etc. Gross generalization, sure, but common when stores buy products.
Macy's never carries more than an obligatory, single pair of ugly brown pumps in size 11 either. And when it comes to finding my size shoes, I know that I'll have less competition for the few size 11s Nordstrom orders if I shop at a Nordstrom in a more Asian area than in a more African American area. Not all Asian feet are small and not all African American feet are large. But more African American women (and non-Asian women generally, for that matter) have size 11 feet and thus, we all have to duke it out for fashionable footwear.
As some commenters to the post said, they know not to shop for Mexican cheese in a Chinatown Safeway because they're going to be more likely to find it in a more heavily Hispanic area where demand for such cheese is higher.
Using sales records to determine the demand for particular styles, sizing, and products isn't stereotyping, is it?