The DRM for games is altogether another beast than DRM for movies or audio. Games are interactive so while cracking them should in theory always be possible (unless they are server based), the cracked version represents a possible threat to the users. Did really someone crack the software for the fun of it or is it malware? With movies such concerns are limited to exploiting bugs in movie players, so attack surface is much lower. Also, all one needs to do is capture the output and write it to file. The "hack" is quite trivial with proper equipment.