Like all of the examples, a Sunday Farmer's Market has a chicken-and-egg problem in that it doesn't work without a critical mass of both supply and demand, buyers and vendors. Buyers don't want to go to a market without vendors, vendors don't want to set up in a market without buyers.

A directory has no chicken-and-egg problem. You have a list of businesses, who don't have to set up at your market at all since there isn't one. Any buyer that shows up at your directory can get value from it, since you're just pointing them to the business somewhere else.

You facilitate no transaction. You're not even transaction-focused, you're research-focused, with reviews and alternatives and all that. Vendors don't have to set up in your market, you can simply create their listing for them since it's just a directory. You're the Yellow Pages, not the Farmer's Market.

There's nothing wrong with that, but this series of articles doesn't apply to your site, as it's not a marketplace.