dmomo writes: Amazon.com's Price Check allows shoppers to scan items in brick-and-mortar stores to instantly compare prices. Some retailers are protesting, saying that they cannot compete so long as Amazon.com has a tax advantage. While we see growth year over year in shopping, I don't see physical stores going away any times soon. Could this backfire on Amazon as we see increased efforts by the big-box retailers to lobby for new tax laws regarding online purchases? Or, will that pale in comparison to the revenue this app brings in, given the advantage Amazon already enjoys in lower costs (and therefor smaller margins) and higher volume?