It's very easy to see why Blizzard wouldn't support account detail changes. It would make account stealing/selling much easier, so why would they condone such practices?
It's also easy to see why the accounts need to be in your name. You may not always be with your wife/husband/girlfriend/boyfriend/significant other, so who gets the account if one side decides to leave? You are protecting yourself by having everything in your name anyway. A child under your care is different, seeing how you are making their decisions for them.
With so many of these posts I think we should have a big, bold sticky that says: Before beginning multiboxing ALL OF YOUR ACCOUNTS NEED TO BE UNDER THE SAME NAME. Period.