The reason why it's worth it is because its search works really well. I've tried DuckDuckGo, Bing and always subconsciously ended up back at Google. This is the only search service I've used that works better than Google search and I think it's a combination of them not putting ads on the search and the way they let you tweak the search to block poor quality sites. How much it costs them or how much google profits vs your payment is not really relevant to me. It's the best working search engine in my opinion.