I don't rest my foot on the pedal, so there isnt a worry about that, and it all depends on how/where you drive,
I drive the freeway everyday (roughly 200kms a day) and I just find it easier with all the people that love to slow/stop/go/slow/stop/slow all over the freeway to use my left foot, different strokes for different folks.
Its just one of those things, I grew up racing Karts and it kind of carried over to driving and now I'm ampidextrous? (spelling?) with my feet for the most part (I also have monkey toes, I can grip stuff with them, its kind of freaky.)