It's very good that you're in the sort of position where you can make a stand on that sort of thing - but I'm not quite there myself. In any case I do like a shared space ("office" was maybe incorrect in my original comment) but for people to be productive everyone needs to be just a little bit more considerate than if they had their own office.
If it is a problem there is simple solution - private office, remote office or I fire the company. Simple. Effective. And why would anyone want to share office - I have no idea.