Dive Brief:

• REI's online sales overpowered competitors Backcountry and Walmart-owned Moosejaw the week up to and including Memorial Day, despite all three offering similar sales, according to Edison Trends, a Silicon Valley firm that analyzes e-commerce patterns.

• The outdoor co-op's peak sales days were on May 18 and 28, and outpaced its own May pre-sale average by 600%, according to the report, which was emailed to Retail Dive. That's down from last year, when peak days were 650%-700% higher. 

• The retailer appears to be gaining on those competitors online, though. REI grabbed 82.5% of market share in its category, compared to 14% for Backcountry and 3.5% for Moosejaw, according to Edison Trends. Last year REI took 79.7%, Backcountry 15.7% and Moosejaw 4.6%.

Dive Insight:

With its 2015 #optoutside campaign, REI shook the retail world and shocked its own reluctant CEO when it grabbed attention by shutting down on Black Friday rather than holding a massive sale. After garnering kudos and awards without taking much of a sales hit, the co-op retailer has never looked back. In fact it has doubled down on the concept with added events and a dedicated search engine.

It's true that #OptOutside has narrowed the company's opportunity for blockbuster sales, and that may be why its Memorial Day sale is REI's biggest, according to Edison Trends. But the campaign is also now an element of a wider brand proposition that reflects core values of environmentalism, appreciation of nature, female empowerment and authenticity that may in part explain its market advantage.

The opposite appears to be occurring at Moosejaw, which was acquired by Walmart last year as part of a wave of e-commerce purchases designed to capture a younger, wealthier consumer segment that typically shops elsewhere. Moosejaw's online traffic dropped 7% in the past year, according to ComScore data cited by the Washington Post. 

Other e-tailers purchased by Walmart last year also appear to have slipped, according to that report. Walmart has sheltered them by operating their brands as standalone sites or selling only on Jet and not Walmart.com. A close association with Walmart is a mixed bag for the brands, even for those customers who happily stick around, experts have told Retail Dive. Walmart has built a formidable distribution network and has the deep pockets to help these young companies scale. But aligning too closely with the brand could hurt their ability to sustain the higher price ranges and it's not clear how much defense Jet can provide.