[disillusion]

No, it does't allow comments. Fortunately, a project README has more then enough room for any remarks. Yes, you're better off putting numbers in strings. No big deal.

But also:

JSON files are easily readable by default, in a lot of languages. Knowledge about (the limitations of) JSON can easily be assumed. Alternatives like YAML, TOML or any of the others all have their own idiosincracies.

And non-programmability is a good thing. It might be more verbose, but you don't have to fire up a javascript environment or bash interpreter or some such just to read a configuration file. And separate code paths are very explicit since that will mean separate objects or even files.