The ~ is on the left side of the keyboard (at least my US-style keyboard), so touch typists will use the right shift key...

There are people who use the right shift key? Seriously?

Huh. I use the right shift key about as often as the right alt and right ctrl keys -- which is to say, somebody could sabotage those keys as an April Fools joke so that pressing them does nothing, and it could be five years or more before I notice, depending on when I finally get around to cleaning out my keyboard thoroughly (as opposed to just quickly running an ISO long narrow object between the keys to get most of the hair out, which is what I usually do).