This is not about competition; the article is about the practice of people going to a retail establishment, taking the salesperson's time to collect all information to make a purchase, then popping online on your smartphone and buy it from an online site that can sell it for less since they do not provide the sales support.
Are you ethically OK with that practice?
The article is about people who look up products on their smartphone while shopping for them in a retail store. The article says that when help they're helped by a sales associate, they're more likely to buy in-store than online.
Of course I'm "OK" with people browsing in a store, or several stores, talking with salespeople, and buying from the cheapest merchant, whether it's online or brick and mortar. It's called being a smart consumer.
If I go to an electronics store and talk to a sales rep, and then go next door to another store and find it cheaper and buy it, there's also nothing wrong with that.
You seem to be stuck in this stone aged view of retail where brick and mortar are the "real" stores, and online merchants are illegitimately infringing on a market that is not theirs.
It's the merchants job to win the sale, and if they don't, because of price or otherwise, TS.
Your mindset reminds me of the Occupy movement. A salesperson is somehow "owed" the sale just because he talked to a potential customer for five minutes even though his price is higher, and it's "unfair" that he doesn't get the close because an online store is able to offer it cheaper even AFTER shipping costs. This may be the standard narrative at the Barack Obama School of Business, but it has absolutely no grounding in the real world.