Actually no, many studios in Japan distribute 
their cels on purpose. Heck, there's shops all 
over Japan that sell the cels right out in the 
open. 
You see, lots of animation studios, including 
Disney, Warner Bros. & many anime studios will 
either sell the cels when done with the 
movie/show or destroy them. But unlike most 
American animation, A lot of Japanese animators 
find fan art flattering. I was at an anime con 
where there were a few animators from Japan & a 
couple fan cel artists with tables. There didn't 
seem to be a problem at all.