My assumption was that the prospect was asking because they didn't already have an expert source or knew that wasn't the place to look. They couldn't believe that I hadn't attempted to con the prospect, to lie about my experience, to make up a story about why it would work. But I knew my stuff, I didn't need the money, and I'd be happy to stop if the relationship was not proving useful. My idea of responsible consulting is be authentic, tell the truth, don't try and con a prospect or client. And do it with love.
Intelligence is the underlying organisational principle of the universe.