I don't quite get that. What would a majority "don't care" vote imply? Surely it's like assuming someone not voting doesn't care? I know plenty that were convinced that not voting was the strongest way to show it was a ridiculous vote. "Don't care" has too many options to be meaningful.
The Allam's have sort to find the opinion of the silent majority. If we only have 7000 votes and say, to be generous, its split close on 50/50 than no one can claim 3500 votes represent a silent majority.
Surely a majority 'don't care' vote means just that. They don't care either way about the name change. Not sure what other meanings it can have!
In a fair vote it would imply that it really doesn't matter in the grand scheme of things and that people should just move on what ever happens. Having the abstaining votes count as not caring is making an assumption that all of them knew how to vote in it, and that assumption doesn't need to be made. You'll still get people who didn't know how to vote and cared, and people who don't care who couldn't be arsed to vote, but the result would be a fairer representation of the support as a whole. Obviously the club would still be best to act on the majority decision out of the 2 names, but purely for gauging opinion from as big a sample as possible I'd want the 3 options to be there.