I know this sounds like a proposal for SCP-001, and I may use this concept for a proposal sometime in the future, but for now, I feel like this concept could actually provoke some interesting discussion and theories on this site.
Ok, so my theory is that the earth, or at least some sort of entity within the earth, readily creates anomalous entities and phenomena around the earth. The reason for doing so? It's not human, so its hard to explain its reasoning in human terms, but perhaps the entity or entities are intentionally trying to change the earth into some sort of 'Anomaly World' where they can survive. Or maybe we're just in the way of their experiments or something.
This could potentially explain the origin of THOUSANDS of scps, like 682. Perhaps 682 was originally supposed to be some sort of weapon to destroy the majority of life on earth so that the entity/entities could move in and alter the physics of our world more easily. Think about it. Almost every single object contained by the Foundation is in some way harmful to humans or life on earth.
It's also possible that the entity/entities responsible alter people's brains so they try to create or propagate anomalies, which could explain groups like the Church of the Broken God, MCD, Dr. Wondertainment, etc. It could also explain why groups like the Foundation exist, like perhaps the being/beings responsible for anomalies tried to change a person to think a certain way, but it didn't work, and it backfired on them.