So let me give a hypothetical. Say my grandmother
takes a really
awesome photograph. She doesn't want to
create a Wikipedia or Commons
account. In fact, she doesn't even have a computer. Furthermore, she
doesn't want her name up on the Internet. But she is willing, after
some persuasion from me, to license her photo under Sharealike 1.0.
Can I put this image in Wikipedia and/or Commons without lying?
I see no problems, just say "Created by my grandmother who agreed to
license it as CC-SA-1.0."