Long before Blockbuster became as common as Mc Donalds, the porn industry started putting thier movies on videotape. It also gave adult bookstore owners a new lease on life, as they could use the videos as the main attraction for getting clientele into thier stores. The main reason the porn biz is so successful online is that they have a product that people want, and want the conveinence to enjoy it in the privacy of thier own homes. If you look at some of the other e-businesses, and apply the formula, many businesses come up short, and for varying reasons. Com was pushing pet food and supplies.
Most people can buy pet food either at the supermarket, or at the local pet store.
And, when they buy it, they will have it right away. The same problem applies for a lot of e-businesses. For most basic items, the internet is not a good fit because the conveinence is not there, and delivery costs are prohibitive. What will do well on the net are specialty or niche items, that are not available everywhere, and that have loyal markets. While you can buy a computer just about anywhere, getting the parts to upgrade may not be easy to find, especially if you live in a rural area.