In e-commerce, Amazon looms largest. Leaders from a number of retail startups—Casper, ipsy, Shippo, and others—participated in an open discussion about their businesses at a Tuesday breakfast roundtable at Fortune’s Brainstorm Tech conference in Aspen, Colo. Amazon (AMZN, +1.30%), whose stock price soared above $1,000 per share for the first time this year, remained the inescapable center of gravity. Julie Bornstein, chief operating officer at Stitch Fix, a clothing subscription service, said that people suffer when a single company monopolizes a market. “It’s a danger to consumers to let Amazon use AWS [Amazon Web Services, the company’s cloud business] to price everyone out of the business,” she said. (Amazon’s margins for web hosting far exceed retail, a position that allows the company to subsidize its e-commerce business.) Laura Behrens Wu, CEO of Shippo, a startup that makes logistics software, agreed and identified what she considered a weakness in Amazon’s approach. “What Amazon’s not doing well is using Instagram, Facebook, and Twitter to create its own brands and voices,” she said. “Who enjoys thinking about Amazon in their private life? No one does.” Read more at Forbes.