"Items that have been moved should disappear otherwise it crashes the server as items increase..." That is the very worst idea in the world. Just amalgamate piles into a few rather than ten million individual ones. Doing that would ruin the immersion by having players doubt whether an item on the ground will randomly sublimate into the atmosphere or not - it also goes against the persistent-world design perspective by making things more instanced/ephemeral. Camping at one spot and waiting on spawns is a very awkward and inelegant thing to do. What should happen instead is that the percentage of good items per drop should rise, along with the respawn period. Then it's less tempting to camp at one place and it would feel slightly more realistic - "okay, we've scavenged everything, let's move on the the next hut".