Regular shoes are regular shoes... Bike shoes are bike shoes.... I recently purchased a pair of Specialized Sonoma bike shoes that use SPD cleats recessed a bit so you can walk around on comfortably (on carpet) The cleat still hits concrete and tile floor just a little bit. I tried using my new bike shoes one full day at work and gave up. They are great for short walks, but not all day.

Mega feet? I have size 14 feet, which translate to size 47/48/49 depending on shoe manufacturer. Specialized has a roomy 48, Shimano generally is tight and would require my purchasing a size 49, but good luck finding a 49. I would purchase from a real store rather than on-line.

There are casual bike shoes that don't have the look of mountain or road shoes. The section to attach a cleat is usually behind a rubber oval that needs to be removed.

Put cleats into regular shoes... I don't think it's a good idea. My Sonoma shoes ran only 73 bucks, we're not talking the high prices associated with road racing shoes. Look around the web sites first and see what catches your eye and falls within your price range.