No need to appeal to roads or police,

where is the money in that private deal coming from if not the state? And what it is the state if not and element (for best or worst) of how we, as a society, have chosen to organize?

You can use private currency. No need to use government issued money. Yet tax laws make no distinction between trade involving government issued currency and trade involving wholly private currencies/properties. And you're making a fallacy of composition in claiming we as a society have decided something. What you're really arguing is that the majority has decided something and that they have a right to force their will on everyone.

" the majority has decided something and that they have a right to force their will on everyone."

Well, it's not your proposal that we organize society following your favourite principles instead?

The only principle that I want society to follow is to not rob others of their right to their person or property. Everything else can be organized through voluntary association.