The rapid development of e-commerce leads to a number of new problems related to the definition of e-commerce prospects and the future of traditional trade, the regulation of national and cross-border e-commerce, the evaluation of the effectiveness of e-commerce in different business areas and the impact of e-commerce on global economic processes, etc. They dictate the need to revise and refine traditional models of pricing and competitive behavior of market participants, taking into account the specific features of electronic markets both from the standpoint of theoretical modeling and in the form of empirical data analysis. The article discusses the causes of price dispersion in electronic markets, which contradicts the generally accepted opinion about their high competitiveness. The study of books prices in the largest Russian online stores, conducted by the authors, confirms the conclusion about the high dispersion of prices for homogeneous/identical goods. The analysis of empirical data and theoretical models of spatial differentiation, allows the authors to conclude that the trademark and brand are the determining factors for buyers in choosing online store and, as a consequence, determine the difference in prices for the same goods with a wide offer of different market operators. The power of influence of the online store brand on the choice seems to be stronger than in the offline business. As an additional factor affecting the growth of prices, the article highlights and presents the usability of the site and customer-oriented sales.