There is NO WAY that eBay will voluntarily shut down as long as they are making money.
As for Ecommerce, it is here to stay. Ecommerce is not a SPECIAL form of commerce. The web, mail order, brick and mortar, infomercials, magazine ads or whatever are all just different ways of selling products. The web is very convenient and cheap. On the web, a seller can fully describe their products without the limitations of a 1 page ad, or a 30 second commercial. Ecommerce will only grow larger, and it may be very common in the future for someone in the USA to order direct from China, the UK, Brazil or wherever, just as if both parties were in the USA. We are only seeing the beginnings of this.
Brick and mortar is going to have a hard time. It is expensive to maintain and staff those stores, and it is much more convenient to order what you want online and just have it delivered. Add the fact that online prices are cheaper, and you will see the demise of several types of brick and mortar stores.
Video stores are almost gone, electronics stores are fading fast, department stores are having problems, etc. Lots of empty spaces will have to be filled. Some categories are relatively safe: Grocery Stores, Home Improvements, Furniture, Appliances, Clothing, Restaurants, etc. Anything that is impractical to ship (example, fresh meats) or very expensive to ship piece by piece (example, refrigerators) will be OK for the foreseeable future. So will things like clothes, where sizes can run larger or smaller, or where people want to try the item on before they buy it. Everything else is up for grabs.
If eBay closes, there is always Amazon. Not to mention a hundred other sites that would step in to fill the void.
And if Ecommerce folds, it will only be because it is replaced with something even better. If that happens, we will all adapt to the new platform, or go out of business. Milk used to be delivered. There were once butcher shops, shoe repair stores, ice delivery, vinyl records, horses on main street and three television networks that had a monopoly on home entertainment. Nothing lasts forever.
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