Hey, I'm back, wonderful lurkers and/or posters of Dev!
I have a really interesting question (as stated in the title), why can't you use "String Subtraction", and "String Division" in most programming languages? (I say 'most' because I know there are some languages which allow the former).
Why can't we say, do this:
"Hello, World!" - ", World" // "Hello!"
or what about
"Hello!" / 3 // "He"