I'm beginning to see an increase in copying from my public tree to one where the copier has made his/her tree private.
One reason I made my tree public was to connect with others doing the same or similiar research. It disturbs me to see others use my work and then block attempts or ignore requests to access their work.
If they want to keep their tree private fine, but they should at least be required to get permission to copy anothers work.
I'm venting, sorry - I'll just take mine private and be done with it.