"The HFPA is extremely disappointed that the MPAA has unfairly decided to continue the screener ban on organizations outside of the Academy of Motion Picture Arts and Sciences," HFPA president Lorenzo Soria said.
MPAA claims that the screener ban is implemented because of movie piracy. Many smaller production companies claim that the real purpose is to get the award voters to see only the big budget movies that are running in their local movie theatres and to get rid of small-scale productions in awards shows.
Basically critics and various movie industry associations object the ban because by associating the screener ban with fight against the movie piracy, MPAA is pretty clearly stating that critics, actors, etc who get the screeners are possible movie pirates that shouldn't be given something as valuable as a good-quality DVD copy of the movie thats going to hit the small screen only after two to three month wait.
Source: Backstage.com