Sometimes you need to deliberately not quote, though. For example, an output of a program might be a list of files, which I then might want to operate on using

Sometimes you need to deliberately not quote, though. For example, an output of a program might be a list of files, which I then might want to operate on using "for filename in $files". If I do this then I must have a guarantee that the files do not have spaces in them, but this is usually not a particularly onerous requirement for a closed system that doesn't have untrusted filename inputs. Splitting data using text separated by whitespace is part of the essence of Unix (see TAOUP). If you want to ban this kind of thing too, then you might as well not permit shell scripting at all.