Not that I know of any incident where he has slipped while bowling! I was told he wears two different colours of shoes! He sports two different brands on each of them and the reason he gives is his leg sizes are different. But soon this is catching up with young boys as a style statement!
So, now I might have to go to shoe shop to buy two different pairs of two different colours so that my son can wear his one pair of shoes! Probably sooner the time might come when the manufacturers would catch up with it and have two different colours for a single pair to ease our job!