Hopefully most of us can agree that original audio should be included on a DVD and if they want to give additional audio options so much the better.
Those that don't want to listen to other mixes could stick to the original audio.
I'm not a mono fan per se, but I think the points about "created" audio are sometimes valid.
This came up recently with the new Bond DVD supposedly going to be in 5.1 - word about whether the original mono audio will be included is not known.
Fans pointed out that Thunderball does not have an English 1.0 track when they put out the 5.1 track. Fair point.
I don't think that original audio purists should get too high on their horses either. If they want to listen to Thunderball in original audio, buy a old 50's theatre speaker and put that in your home theatre. Enjoy!