I am all for expanding our support base and encouraging neutrals to attend, but I really don't think it would help the atmosphere one iota!
Classic example is the cup final... I bought six tickets for two ST holders... each of us brought two neutrals.
The Cup final experience was amazing and I wouldn't change it for anything... but the large number of neutrals had a nullifying affect on the volume of our support.
That said... I truly am all for looking at ways of increasing our support... ... but I genuinely don't think it would affect the atmosphere positively at all... ... what it would do, is increase our funds, which is no bad thing.