I'm going to guess wearing bicycle shoes all day is bad for your feet. They are designed to be firmer and less flexible to transfer power to the pedal--not conducive to walking and standing. Plus, you'll "click" all the time. DH has some spinning shoes that are recessed and don't "click" but my Nashbar sandals definitely do.
I use SPD's--DH switched pedals this year and discovered they aren't compatible with our winter spinning bikes, so he had to buy a second pair of shoes. Just a thought.
"Well-behaved women seldom make history." --Laurel Thatcher Ulrich
'09 Trek WSD 2.1 with a Brooks B-68 saddle
'11 Trek WSD Madone 5.2 with Brooks B-17