Catalog merchant or mail-order retailing has been known for several hundred years and it did NOT make any global revolution (however, there are some local exceptions). As well as trading companies which do not have their own stores and showrooms.

It is customer self-servicing which is a novelty. The technical possibility for its mass application has emerged along with the Internet. 

The ability to arrange and make a purchase by themselves (and it doesn't matter whether goods are delivered or should be picked up somewhere) makes much less stress and much more comfortable situation for consumers as compared to brick and mortar stores.

It is here (and nowhere else) where the secret of e-commerce attractiveness and vitality lies. In spite of seemingly obvious disadvantages like a long distance to the warehouse or difficulties with obtaining pre-purchase advice.

The joy of eliminating of the evil of human-like sales organization outweighs everything else.

A business providing its customers with a convenient opportunity to do without salesmen gets a tremendous competitive advantage.

It also gets a bigger market share. For the time being.

In several years, the self-service option will become a must to survive in highly competitive markets.