The Walmart (NASDAQ:WMT | WMT Price Prediction) pullback is the story consumer staples investors are talking about this summer, and it flows through Fidelity MSCI Consumer Staples Index ETF (NYSEARCA:FSTA), Consumer Staples Select Sector SPDR Fund (NYSEARCA:XLP), and Vanguard Consumer Staples Index Fund (NYSEARCA:VDC) in surprisingly different ways.