I'm with Artstream on this one.
They don't pull into your driveway and ask to see the inside of your home because they are thinking of buying one. The person asking may not appreciate the response but the easiest thing to do is to suggest they see the dealer as you are in the midst of unpacking and typically don't give tours anyway. You consider it an extension of your home. You can also suggest they will understand when they acquire one of their own how awkward it can get.
When we are camping it is different - the others folks there are also doing the same, and it just comes across as different. At my home I want my safety and privacy.
Barry