Report: In-store Wi-Fi boosts customer loyalty, sales Retailers that offer in-store Wi-Fi benefit from increased customer loyalty and sales, according to a new study by IHL Group, EarthLink Holdings and AirTight Networks. The study found that nearly half of retailers saw a boost in loyalty and a 3.4% increase in sales after providing in-store Wi-Fi for employees, and 28% reported increased loyalty and a 2% sales jump after adding in-store Wi-Fi for customers.Progressive Grocer