[bmacho]

> The way that this syntax (see bash, zsh, fish, etc) usually work is that these lists are separated by spaces.

And programming languages that have variables, string type, and function calls do the opposite. In C, Python, JavaScript etc, in order to start a program you make a function call with a list of strings.

> Choosing space for a very common thing in your language often makes sense,

Not interpreting space separated things as strings but as keywords (built ins, variable names, literals) makes more sense for bigger programs.