I think you are missing something. It isn't about seeing a picture. It is about a fantasy. It is a daydream. The more they "know" and view one person, the deeper that fantasy can become. People are able to delude themselves into a mindset of "if I keep interacting with her, what if she realized how cool I am and we actually got together" or similar.

This gets into what is real and the power of anticipation. There have been a lot of studies that show the biggest endorphin bump for a vacation is in the planning, not actually going and experiencing the locale. This is going to really change as VR matures. People will be having lots of experiences at home in a very immersive way. This includes front row at a concert, walking tours of a far off city or attraction, and obviously VR porn integrated with mechanicals. We have vivid dreams all the time and they are not "real", I think these things will feel even more real for the immersion.