Invent a time machine and have your own feet bound as a child.

Seriously, though, this is a good question. I still ride on platforms, and this size question is one of the main thing that's kept me from looking more into clipless (finances being the other). I'm an 11 or 11-1/2 EEEE, and seeing so many people complain about a lack of wide options in SPD-compatible casual shoes maks me think any search would be fruitless. Seems there's gotta be a way to impart upon the manufacturers that there's a real demand for this kind of product...