Yelp, YellowPages, etc. spend a TON of money on Google ads each year. The vast majority of small businesses don't.

I'll let you draw your own conclusions from that.

Usually this means there is no SEO, as in, in the business you're searching there are actually no relevant companies with actual websites.
Of course this doesn't mean there aren't businesses in that search, just that they aren't online. Which is why you get a yellow pages listing as the top result.

Potential market for you right there, provided the niche isn't too small. Provide an website service for companies in the searches you mentioned.

The sites you mention are review or directory sites. This usually means that the business has no site to SEO, so the search engines return what they think may be useful.

Some businesses skip having their own website in favor of a Facebook page, Blogger blog or some other presence. A little shortsighted in my opinion, but it's their business.

Believe it or not lots of businesses still don't have websites. In many cases when those things pop up first that is why - there is no direct website for the business.

Thanks guys for the tips ;-)

I thought most businesses would have websites by now - this is 2014 after all ...