>>Wow, I can't believe that there's no one else (other than me and Naomi) who thinks this is a bad design and counter-intuitive!!! Well, no one else who's replied anyway.

Think about it this way guys ... paper forms with checkboxes. Users know how to use checkboxes on a paper form! Why would an electronic version of that be any different?
>>
You made the point well, Bonnie and I agree with you.
However nothing is bad design if the person who will be using the system think it's good design.
One of our most financially succesful clients, who makes tons of money running their business, has asked us to do some pretty weird things with computer screens and after years of using them, they think those screens are just nifty!
They make me shudder every time I look at them.

Once I've explained my point - as you did nicely here, I don't argue user interface standards - especially with people who can write big checks.
You wind up annoying yourself, possibly losing money and convincing no one.