Few things annoy internet users quite as much as unwanted, intrusive ads — a principle that some online retailers understand better than others.

Particularly disruptive for e-commerce merchants are pop-ups, banners and other ads leading to competitors’ sites that can appear without their consent or knowledge due to malware on customers’ browsers.

Namogoo, a technology company that works with clients like Asics, Hudson’s Bay Co. and Schuh to combat these unauthorized injected ads, analyzed hundreds of millions of web sessions across the U.S. and Europe during the holiday season (Nov. 22 through Dec. 24, 2018), and found that 25 percent of online shoppers encountered this phenomenon, which it has coined “online journey hijacking.” During the pre-holiday season (Oct. 21 through Nov. 21, 2018) this share was 18.2 percent of shoppers.

According to the study, mobile traffic picked up considerably over the holiday season in both the U.S. and Europe, growing 47 percent in the former and 50.5 percent in the latter, compared with previous weeks. As supported by earlier holiday retail data, consumers increased their online purchasing over the period, too: mobile orders in the U.S. saw a 93.7 percent lift, while desktop orders rose 85.3 percent.

The company found that infected users who had unauthorized ads blocked converted at a rate 2.5 times higher than users whose browsers weren’t exposed to malware at all, suggesting that the affected group is eager to buy during the holiday season.

This should be of interest to footwear retailers in particular, since the category led the pack in terms of traffic and order increases in both the U.S. and Europe during the holiday season. Orders increased 189 percent in the U.S. and 218.5 percent in Europe over previous weeks. In the States, the gifts and hobbies category saw a bigger conversion boost, but shoe brands followed with a 71.4 percent lift.

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