They're a bit over the top but when you're installing an outlet with an isolation transformer anyway it doesn't really make a lot of difference to add a 110V tap too.
However, the vast majority of shavers and toothbrushes will happily work on anything from 100 - 240V 50 or 60 Hz so it doesn't make any difference which side of the socket you plug it into or what position the slide switch is in.
