It's not just a prospect or customer saying, 'Yes'. These are just instants in time. When a customer checks a box or says 'Yes', it doesn't mean that you now own them and their constant attention. You have them for just a very brief moment. The key to success is how you use that moment.
Permission marketing is about building long-term relationships.
Help people find what they want Permission weakens in the face of confusion. You may love your web site. But chances are it's a horrible place in which to find stuff. Most folks online are not experienced Internet users. To you it may be obvious how to navigate around your site.