The software I have (VLC) can rip DVD audio, but it's a pain in the ass to use. You have your choice of the entire disc at once or one track at a time, but if you do one track at a time, you have to reset all the parameters every time. Format, bitrate, output path, everything. Pain in the ass. Plus, unless they don't give you the choice between Blu-ray and DVD (in other words, you get both no matter what), I'm getting Blu-ray, and I don't have the means to rip Blu-ray to audio.
And it's not just the ease; it's also having the CDs. Dream Theater is one of the few bands for which I have the entire discography on CD, and I'm going to try to keep that going as long as I can. I'm an old fuck. I like having the packaging and all the goodies that come with it. If I'm gonna go through ripping and burning to blank CDs just to play in the car, I'd rather pay an extra ten bucks and just buy the deluxe package.