NEW YORK (TheStreet) -- Latin pop star Ricky Martin headlined Wal-Mart's festive annual meeting on Friday, but he may have been one of the few who were dancing.

Martin's performance followed news that Wal-Mart's longtime chairman and a son of founder Sam Walton, Rob Walton, will step down. Jumping into the role will be 45-year-old Greg Penner, the current vice chairman of Wal-Mart's board, Rob Walton's son-in-law and owner of 4% of the retailer's stock.

Penner joined Wal-Mart as a management trainee and has held a number of positions, including senior vice president of finance and strategy for He also served as chief financial officer for Wal-Mart's Japan unit Seiyu and joined the retailer's board in 2008. 

But with Wal-Mart's stock declining 14% this year, badly underperforming the Dow Jones Industrial Average's rise of 0.3% the past year, and billions of dollars being plowed into projects such as improved online shopping and higher hourly wages for workers, some investors may be concerned that keeping the chairmanship in the family may be to the shareholders' detriment.

At least that's may be their view of the arrangement early on: Shares of Wal-Mart fell 0.4% in morning trading. By 2:52 p.m. EDT, the shares were priced $73.08, down 1.44% thus far for the day.

The Walton family owns close to half of Wal-Mart. With Penner at the helm, Wal-Mart's executive leadership team, led by Walmart lifer and new CEO Doug McMillion, may be apt to favor its own agenda instead of being mindful of shareholder interests.

For instance, Wal-Mart could opt for a future of continued aggressive store rollouts across the country, as it has traditionally done, even as returns from those stores suggest that slowing the pace would be more beneficial to shareholders. 

Another example could be further efforts to bolster employee pay and benefits beyond Wal-Mart's pledge to invest $1 billion in its associates this year. With the continuation of a cushy board arrangement, future hikes in pay may be tougher to get approved as Wal-Mart works to protect its profits, risking damage to the recent goodwill it's built up by raising wages.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.