Anyway, I'd see this idea of yours, but only in two contexts:

10000 gil to warp to the major cities.
Determined amount of gil to any camp based on how far from the city it is.

Because having the possibility to warp everywhere would make Mounts/Hairships worthless, considered the little gap of space between camps and nodes.
That's the way I would implement it, but only if I'm ordered to. By myself, I would leave this idea alone and keep using Animas, Mounts, Airsheeps, Boats and our own Feet to walk around the world. Feels more immersive, butthurt and adventurous than going to a guy asking for teleport, which is boring, easy mode and not satisfactory at all.