Yes, I've seen it. Have you given it a serious look? It looks great in quantity, but would you ever consider purchasing anything for a decent sum from any of them? The only remotely reputable merchant I'm aware of on there is BitcoinStore.

Furthermore, there is noone offering general groceries, household supplies or clothing, just niche approximations of those categories. Also critically lacking are complex B2B services(their professional services section is...well, not much to look at - I certainly would not be investing my business's money in any of them at this time).

If I showed you a list of non-Bitcoin-accepting merchants picked at random, you would almost certainly have the same reaction: you would not trust most of them, because they are all too tiny and you have never heard of them.

You have to realize that the web is a long-tail ecosystem. There are tons of small merchants you have never heard of, while the biggest ones (Amazon, Newegg, etc) are just a few and represent <1%. What you call a "reputable" merchant exclude 99% of all merchants. Plus, the most reputable/biggest merchants will probably be the last ones to adopt Bitcoin (the bigger you are, the less likely you are to adopt a disruptive technology).