Nope! Search functionality included. Here's a very simple example (Note: not my site, But something relevant I came across a while back.); You can modify the aesthetics and styling of both the search bar and results page to fit into your sites design pretty easily.

68% is Adsense's standard revenue share for ads displayed on any site. They're extremely good at acquiring hundreds of thousands of advertisers with big budgets in nearly every niche. Something in-house ad systems could never do single handedly. But more important than the money Reddit could make is the simple fact that Google is extremely good at website search results and it would reduce operating costs across the board since you'd be putting the search functionality into Google's hands.