Never mind the question marks, people- I think I figured out the poster's motivation.

Advantages?

You'll win the favor of the one or two asstroll busybodies on every cycling forum who won't simply ride their own bikes and be nice about everyone else's- they have to assume the role of Utility Police, making sure that every component on your ride is being used as the factory intended.

I use my running shoes to walk as often as I use them to run; hope that isn't some sort of violation of the Shoe Usage Code.