Directory submission

I've been receiving plenty of emails lately from different people regarding web directory submission. The emails are basically offering me to use their online services for my webpage advantage. Some of these directory submissions are free and some don't however, each of them are basically the same helping my website to get more traffic, build link popularity as well as getting the site indexed by search engines. We know building webpage traffic and popularity is difficult and having these free directory submission can potentially help the website's exposure. I don't see why anybody won't use this tools, i definitely would recommend it.