Did you read the same article as me? The word is singularly used in the context of how do you earn money as a project, i.e. sustain the effort. It's a bit of a leap to imply this is impure unless they made some contract stating the opposite or are doing something dark.
Oh yeah, the part where he sold the browser to an online advertising company that just happens to run startpage is purity huh? Damn, Google and Chrome must be saints
You must be one of those guys who reads Philip Morris “articles” on the benefits of smoking and concludes there’s no evidence for harm.