But it doesnt require people to be employed in the numbers that other methods do. What do we do with all these people?
I have a couple of clients (remarkably similar set ups but different products) who are online retailers and both employ lots of staff, and not all at lower levels either. OK, most are pickers and packers from the warehouse, but they also have a few customer service advisers to take phone orders and give advice both are heavily into exceptional customer service hence their success). They employ managers, they both have book-keepers. One has an in house web designer, the other subcontractors to a local firm of web designers - they both pay substantial amounts for hosting and postage and CEO etc - i.e. staff employed by other firms!
Given their turnovers, they are employing similar numbers of people as if the buildings were factories - in fact one of them is in an industrial building that I used to go to as an auditor in a previous job 20 years ago, and they employ more in that factory today than it did 20 years ago as a factory.
Online retailers aren't all spotty kids in their bedrooms. Most decent websites will have bricks & mortar premises and employing plenty of people with varying skills. Just think how many jobs will have been created for web designers, SEO experts, software developers, etc., on the back of websites? Then you have the ISPs, the data centres, the infrastucture, all employing people, many of whom will be higher technical roles.
It wouldn't surprise me at all if online retailing is responsible for employing, directly and indirectly, a similar number of people to the B&M stores it is replacing. It's just evolution. Change happens all the time. Big store B&M has had it's day. You also have to remember that the likes of Comet would have been responsible for the demise of numerous smaller electrical retailers - there was a time when you had smaller chains (Rumbellows, Electricity showrooms, etc) on the High Street - they in turn had replaced the independent owner-managed small shops. In fact, there may be the opportunity for smaller independent firms to re-open once Comet and Currys are gone, to cater for the people who want good customer service and are willing to pay that little bit more to buy from experts rather than school kids who know nothing about the products and don't want to order from the internet.
People have to adapt. Before the industrial revolution, people lives in and around farms and villages. With the Ind Rev, those people moved to the towns and cities for better jobs. Town centres used to be where people lived and where people worked in factories, warehouses, etc - shops were incidental and just dotted around on street corners etc. Then the factories & warehouses left the towns and were replaced by High Street shopping. Then High St shopping was replaced by out of town. Now it's being replaced by the internet. It's just the way things change. You move with it rather than get stuck in the past and pine for things to go back the way they used to be.