Totally wrong. If you have the disc how do you think you can mux in fan subs? The people using these are torrenters, not those that just bought a disc. Yes, there are ways to rip, transcode and remux, but be honest, we all know these subs are for pirated videos.
Are you kidding? Ever heard of VLC? You can play DVD or video files and use any subtitles you want.
"Never give in. Never give in. Never. Never. Never." -- Winston Churchill