I can only speak for myself. I just made my tree private last night due to I had tons of people were just random using all the hard word that I have done on my tree to link to random people in their tree a lot of their information was even linked wrong just because someone had the same last name it does not make it the ancestor you are looking for.
I feel bad for doing this.. but I work really hard with verifying all of my facts and not just blindly linking people just because a Leaf appeared. I also have a lot of photos and family history I would love to share but not for the people that just want to fill up there tree with my hardwork.
At least a thank you or hey do you mind if I use this information..