Sam's Club has introduced new "grab & go" items, with prices starting at $2.74, and a feature that allows customers to skip lines. The move is seen as a challenge to Costco, with some outlets suggesting that Sam's Club is gaining popularity, although it's unclear how Costco will be affected. Some reports focus on specific new products at Sam's Club, while others mention Costco's own deals, indicating a competitive landscape between the two retailers.