Gallery - access and security

It's not clear what security there is to prevent access to the 'Gallery' in Lightroom Web? Does anyone have any answers for the following?

1. The 'Gallery' (under 'All Photos') can be accessed by anyone with the 'Gallery' URL.  What is to prevent crawlers trawling all the adobe URLs and hoovering up all the images and metadata?
2. When I add a shared album by using  'Share in Gallery', the 'Gallery' doesn't seem to honour the shared album settings e.g. 'Invite only'.  Is this the case?
3. Is it possible to password protect the Gallery or control who/what can access it?

Thank you