It's not rocket science, but it's way more than the cashiers are trained or equipped for, and it's potentially a big liability for the corporation. Keeping the books at a national chain may not be any more intellectually complex than doing the books at a small business with one location and a handful of employees, but it's several orders of magnitude more complicated on a practical level.

I'm not a big fan of Whole Foods either, but that's really only because they're a big national chain that behaves the same way as any other big national chain. I admit I shop at supermarkets. I patronize locally-owned natural food stores, farmers' markets and farm stands, but sometimes I just need, oh, say, baking soda; and other times my commitment to buying local and organic produce falters in the face of seasonal monotony or plain absence. Now if I had both a Kroger's (union) and a Whole Foods (non-union, but better selection) locally, that would be a tough choice.