In my opinion, and I've run some pretty big sites, that's a load of rubbish unless (as Lynne said above) they have a backend that'd require multiple locations for the change, or a query. For the majority of vb boards, I'd say it's just admin laziness. Like I said, it takes 5 seconds and a community is nothing without it's members, so I have absolutely no problem with name changes on any of my sites.