Imo there's nothing suspicious about, I am an early adopter and I happily pay for it. It simply provides better results than Google, Bing, DDG and any other search engine I've tried. I'm not a fan of subscription based software/services at all, but for once I think it makes sense when it comes to search queries.

Before I was an avid user of google but seeing the results getting worse and worse made me look for different solutions. For now i'm interested in supporting a search engine that can keep itself above water through my wallet.