Read & Render Only Format
Sometimes the original project should be sent to the client so that he can get output of it but it is important for the artist that no one else can use those features he has used in his project in other ones .Like 3D model, texture, animation and material which can be used for that particular project .So Read and Render only format can help achieve this .
So it is a kinda of copyright for the artist and the company .
Hossam Hassan Sakr commented
if we can export project to .EXE file and the client can walk around and see what is project looks like with all data with out can accesses the models and texture that will help a lot