Let me start off by saying I find this hard to believe. A Google Maps Help thread has one individual claiming that a Yell.com representative claimed that if you don't pay for your Yell.com listing, your Google listing will drop down. Yell.com is a popular UK local search engine.
The Yell representative reportedly said, "of next week, unless you pay for Yell.com, your listing on Google maps will drop down below anyone listed with Yell.com in your area."
Of course, this is not possible, Google would not let Yell.com influence how Google Maps works and ranks listings. In early 2008, there were rumors that Google would buy Yell and in 2005 Yell even powered Google Local UK, but that is long over with.
A Google Maps representative made it crystal clear. Joel H from the Google Maps team said:
Yell.com doesn't control ranking in our search results.
Maybe the poster was confused or maybe the Yell.com representative was confused or a bit crazed. I don't know for sure, but one thing I do know is that Yell.com cannot do what this poster said.
Forum discussion at Google Maps Help.