I thought the hyphen was there to go with "free", even though there are a couple of words in between. If they'd said 'typo-free' without mentioning 'error-free' it would have been ok, wouldn't it?
They claim that it was a genuine mistake, many don't think so. The Wig and Pen (near the Crown Court) bought the sign off the company that was putting in new sewers and water supply lines.
I remember a few years back a company called Pen Island, dealing with fancy pens. Because of the way email does not allow spaces their address was www.penisland &c