If you want your music to be available to a global audience, you need some funding or revenue to promote yourself and to travel to share your music live. Because the record labels and travel industry might not be willing to give away their services for free.
It only requires you to charge IF you want to do something that requires you to (global popularity). Having music globally "available" has no cost, I suspect you are referring to globally popular music. And I think it makes sense for that cost to be beared by the artist since they are the one benefitting and desiring it anyway; no point in asking other people (record labels / travel industry) to do that service for free.