I, too, have yet to experience the poor service fueling some of these negative reviews. One cannot walk into a Wal-Mart and expect it to be like a Nordstrom or a Neiman Marcus. This store has always been clean and the workers have always been polite. My wife and I are comfortable walking across the parking lot at night.
Wal-Mart remains the place to come first if you have a few household items to purchase; a spatula, perhaps, some light bulbs, a gallon of bleach, maybe a game for the kids, or a garden hose. It's not your store for top of the line items, or if you're threatened by a little diversity. And if the latter is the case, why do you even live in Phoenix? Move to Oregon, instead.