As far as conventional wisdom goes, Amazon.com (AMZN -1.52%) is the king of low-cost goods bought online; the Wal-Mart (WMT -0.05%) of the Internet, so to speak.

And that's largely true.

In its rise from a humble online peddler of books into the most feared, and dominant, name in online commerce, Amazon has used its willingness to undercut the competition to send more companies than I can fit in this space the way of the dodo (RIP Borders, et al). However, a recently released report suggests that Amazon's supposed edge when it comes to low prices might not be as strong as some believe.

Inside the battle for e-commerce
Earlier this month, Wells Fargo and online sales tracking firm 360pi unveiled their findings from a full-year analysis of the various online pricing habits of the world's largest e-commerce companies across over 100 commonly offered stock-keeping units. And as you've hopefully gleaned by now, the findings came with their fair share of surprises.

Perhaps the biggest single bombshell was that Amazon.com has lost a sales edge in four important categories to the likes of Wal-Mart and Target (TGT 0.69%). According to the report, both big-box retailers generally offered lower prices online than Amazon in the clothing and shoes, electronics, housewares, and health and cosmetics categories. However, the report also notes that Amazon typically offered the lowest prices when it came to "like-to-like" specifics goods.

This comes as a surprise for longtime followers of Amazon and implies that online pricing software used by Wal-Mart and Target, which scans competitors' prices and adjusts accordingly, has grown sophisticated enough to compete against Amazon's own pricing bots. Specifically, the reports says Wal-Mart's pricing in the four categories sat an astounding 10% lower than Amazon's as of August and that Target enjoyed a 5% pricing advantage as well. The report acknowledges that the pricing survey didn't account for the cost of shipping and taxes, areas where Amazon enjoys advantages with its Prime shipping service and its notorious state tax policies.

Either way, this new report certainly calls into question the conventional wisdom that it's simply Amazon and then everyone else in the online retail space these days.

The bigger e-commerce picture
Still, I think this report misses the point to a large extent by painting Amazon in a negative light on pricing without discussing the overall profit opportunity online.

As Amazon.com and its online peers have been around for a generation now, it's easy to fall into the trap of categorizing e-commerce as a whole as a somewhat mature business. In fact, the opposite is true. When viewed in the broader context of the entire U.S. economy, online retail sales represent a veritable drop in the bucket. See for yourself.


Source: U.S. Census Bureau.

With online sales in the U.S. consistently setting fresh all-time highs, it's also important to understand just how paltry a percentage of total retail transactions they really represent: just 6.2% in the first quarter of the year. And this only reflects the new record figure in a technologically advanced market. Viewed globally, this figure is almost assuredly smaller and it represents a large opportunity for all e-commerce retailers.

There's no question that the stakes are extremely high in online retail. As I've mentioned before, the only free lunch you get in broad-based retail sales are economies of scale. As the global e-commerce boom progresses over the next generation, the companies that control the greatest share of the proverbial pie will have the strongest hand. And both Amazon and Wal-Mart excel in online retail.

Foolish thoughts
Historically, Amazon has always outflanked other online retail outlets. However, owing to the stakes and its well-documented tenacity, it was probably never realistic for the media or investing community to expect a company like Wal-Mart to go quietly into that good night. So while this storyline gives Amazon's dominance in the growing battle for online sales supremacy, it's by no means the end of the story, and that is certainly worth noting.