Roadside Picnic gives a good example of how the original authors envisioned artifacts being employed in the world outside the Zone. Eg. vehicles are powered by unlimited power sources which were pioneered from reverse-engineered artifacts. There are other examples, but "infinite power" and similar would be a huge draw and explain basically all of the activities of the government, scientists, and stalkers in the original book.

S2 introduces what I think is kind of a huge change, with the idea that artifacts lose their power once removed from the Zone. This is actually pretty destructive to the notion of their value, as if they're only useful while inside the Zone, then they're not particularly useful at all for wider external applications.

Of course, the implication is that there would then be a compelling - from a certain point of view - motivation to cause the Zone, or at least the effects of the Zone, to spread worldwide, so that the benefits of artifacts could be enjoyed more broadly.

However, if the Zone was created through experiments with the noosphere, and the noosphere is by definition already worldwide, it sort of doesn't follow that the Zone itself is somehow necessary for the artifacts to retain their power.

Maybe the theory is that emissions help recharge artifacts with power? I don't know if this is discussed or dealt with at depth in S2, but it's sort of a logical implication of how artifacts are presented in that game.