"I will discuss and clarify that gladly with Bobette via email, but not here, with people, which do not even know the Poser Corner or are familiar with the German laws."

You have a poser store and this discussion is taking place among poser users some of which could become customers. I did not know of Poser Corner until this thread but if your site TOS is so flexible, as has been stated, I will cease my browsing of the site. Allowing your merchant to do what they did, and by stating they have the right to trump your TOS you indicate it could happen again, is unprofessional.
I think you'll find that to be the case of most potential customers.

...... Kendra