Why?
Both brand images are associated with cheap crap. I don't want to eat cheap crap.
A good filter to start with is only products fulfilled by Amazon, and a step further, only Prime products. Granted, the due diligence still sucks, but I spend several thousands of dollars a year on Amazon products, and aside from the products that I know are cheap (like $4 phone cases) I've never had any issues.
Wal-Mart also happens to be among the few grocers in my area that consistently stocks plantains (which are among my favorite foods, especially when fried and served with refried beans and sour cream).