Not really. The advertisers who buy the book can still see KRBE's ratings. Most, if not all, ad agencies buy the book as agencies buy almost totally on numbers. So, KRBE isn't missing out on any of that business unless its numbers have really tanked. Given how KRBE's done in the past, it should be doing well enough to get agency buys. Agency buys are what everyone wants because you're guaranteed that money. I've never heard of an agency being a "no pay," and Houston should have plenty of agency buys. Hell, I worked in a sub-250 market 10 years ago, and even we got a few agency buys. We'd bump even our most loyal local advertisers to get an agency's client on!
When it comes to local sales, it's a little different of a story as most of your local businesses don't buy the book, and KRBE can't sell the numbers. I've never been in sales. So, I can't tell you how easy it is to sell local ads without numbers, though local clients are far more likely to buy on a whim or based on the client's personal tastes. A friend of mine who's worked in sales says selling sports is easy, numbers or not, but that was all he had to sell.